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Research Bias 101: What You Need To Know

By: Derek Jansen (MBA) | Expert Reviewed By: Dr Eunice Rautenbach | September 2022

If you’re new to academic research, research bias (also sometimes called researcher bias) is one of the many things you need to understand to avoid compromising your study. If you’re not careful, research bias can ruin the credibility of your study. 

In this post, we’ll unpack the thorny topic of research bias. We’ll explain what it is , look at some common types of research bias and share some tips to help you minimise the potential sources of bias in your research.

Overview: Research Bias 101

  • What is research bias (or researcher bias)?
  • Bias #1 – Selection bias
  • Bias #2 – Analysis bias
  • Bias #3 – Procedural (admin) bias

So, what is research bias?

Well, simply put, research bias is when the researcher – that’s you – intentionally or unintentionally skews the process of a systematic inquiry , which then of course skews the outcomes of the study . In other words, research bias is what happens when you affect the results of your research by influencing how you arrive at them.

For example, if you planned to research the effects of remote working arrangements across all levels of an organisation, but your sample consisted mostly of management-level respondents , you’d run into a form of research bias. In this case, excluding input from lower-level staff (in other words, not getting input from all levels of staff) means that the results of the study would be ‘biased’ in favour of a certain perspective – that of management.

Of course, if your research aims and research questions were only interested in the perspectives of managers, this sampling approach wouldn’t be a problem – but that’s not the case here, as there’s a misalignment between the research aims and the sample .

Now, it’s important to remember that research bias isn’t always deliberate or intended. Quite often, it’s just the result of a poorly designed study, or practical challenges in terms of getting a well-rounded, suitable sample. While perfect objectivity is the ideal, some level of bias is generally unavoidable when you’re undertaking a study. That said, as a savvy researcher, it’s your job to reduce potential sources of research bias as much as possible.

To minimize potential bias, you first need to know what to look for . So, next up, we’ll unpack three common types of research bias we see at Grad Coach when reviewing students’ projects . These include selection bias , analysis bias , and procedural bias . Keep in mind that there are many different forms of bias that can creep into your research, so don’t take this as a comprehensive list – it’s just a useful starting point.

Research bias definition

Bias #1 – Selection Bias

First up, we have selection bias . The example we looked at earlier (about only surveying management as opposed to all levels of employees) is a prime example of this type of research bias. In other words, selection bias occurs when your study’s design automatically excludes a relevant group from the research process and, therefore, negatively impacts the quality of the results.

With selection bias, the results of your study will be biased towards the group that it includes or favours, meaning that you’re likely to arrive at prejudiced results . For example, research into government policies that only includes participants who voted for a specific party is going to produce skewed results, as the views of those who voted for other parties will be excluded.

Selection bias commonly occurs in quantitative research , as the sampling strategy adopted can have a major impact on the statistical results . That said, selection bias does of course also come up in qualitative research as there’s still plenty room for skewed samples. So, it’s important to pay close attention to the makeup of your sample and make sure that you adopt a sampling strategy that aligns with your research aims. Of course, you’ll seldom achieve a perfect sample, and that okay. But, you need to be aware of how your sample may be skewed and factor this into your thinking when you analyse the resultant data.

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research results bias

Bias #2 – Analysis Bias

Next up, we have analysis bias . Analysis bias occurs when the analysis itself emphasises or discounts certain data points , so as to favour a particular result (often the researcher’s own expected result or hypothesis). In other words, analysis bias happens when you prioritise the presentation of data that supports a certain idea or hypothesis , rather than presenting all the data indiscriminately .

For example, if your study was looking into consumer perceptions of a specific product, you might present more analysis of data that reflects positive sentiment toward the product, and give less real estate to the analysis that reflects negative sentiment. In other words, you’d cherry-pick the data that suits your desired outcomes and as a result, you’d create a bias in terms of the information conveyed by the study.

Although this kind of bias is common in quantitative research, it can just as easily occur in qualitative studies, given the amount of interpretive power the researcher has. This may not be intentional or even noticed by the researcher, given the inherent subjectivity in qualitative research. As humans, we naturally search for and interpret information in a way that confirms or supports our prior beliefs or values (in psychology, this is called “confirmation bias”). So, don’t make the mistake of thinking that analysis bias is always intentional and you don’t need to worry about it because you’re an honest researcher – it can creep up on anyone .

To reduce the risk of analysis bias, a good starting point is to determine your data analysis strategy in as much detail as possible, before you collect your data . In other words, decide, in advance, how you’ll prepare the data, which analysis method you’ll use, and be aware of how different analysis methods can favour different types of data. Also, take the time to reflect on your own pre-conceived notions and expectations regarding the analysis outcomes (in other words, what do you expect to find in the data), so that you’re fully aware of the potential influence you may have on the analysis – and therefore, hopefully, can minimize it.

Analysis bias

Bias #3 – Procedural Bias

Last but definitely not least, we have procedural bias , which is also sometimes referred to as administration bias . Procedural bias is easy to overlook, so it’s important to understand what it is and how to avoid it. This type of bias occurs when the administration of the study, especially the data collection aspect, has an impact on either who responds or how they respond.

A practical example of procedural bias would be when participants in a study are required to provide information under some form of constraint. For example, participants might be given insufficient time to complete a survey, resulting in incomplete or hastily-filled out forms that don’t necessarily reflect how they really feel. This can happen really easily, if, for example, you innocently ask your participants to fill out a survey during their lunch break.

Another form of procedural bias can happen when you improperly incentivise participation in a study. For example, offering a reward for completing a survey or interview might incline participants to provide false or inaccurate information just to get through the process as fast as possible and collect their reward. It could also potentially attract a particular type of respondent (a freebie seeker), resulting in a skewed sample that doesn’t really reflect your demographic of interest.

The format of your data collection method can also potentially contribute to procedural bias. If, for example, you decide to host your survey or interviews online, this could unintentionally exclude people who are not particularly tech-savvy, don’t have a suitable device or just don’t have a reliable internet connection. On the flip side, some people might find in-person interviews a bit intimidating (compared to online ones, at least), or they might find the physical environment in which they’re interviewed to be uncomfortable or awkward (maybe the boss is peering into the meeting room, for example). Either way, these factors all result in less useful data.

Although procedural bias is more common in qualitative research, it can come up in any form of fieldwork where you’re actively collecting data from study participants. So, it’s important to consider how your data is being collected and how this might impact respondents. Simply put, you need to take the respondent’s viewpoint and think about the challenges they might face, no matter how small or trivial these might seem. So, it’s always a good idea to have an informal discussion with a handful of potential respondents before you start collecting data and ask for their input regarding your proposed plan upfront.

Procedural bias

Let’s Recap

Ok, so let’s do a quick recap. Research bias refers to any instance where the researcher, or the research design , negatively influences the quality of a study’s results, whether intentionally or not.

The three common types of research bias we looked at are:

  • Selection bias – where a skewed sample leads to skewed results
  • Analysis bias – where the analysis method and/or approach leads to biased results – and,
  • Procedural bias – where the administration of the study, especially the data collection aspect, has an impact on who responds and how they respond.

As I mentioned, there are many other forms of research bias, but we can only cover a handful here. So, be sure to familiarise yourself with as many potential sources of bias as possible to minimise the risk of research bias in your study.

research results bias

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research results bias

The Ultimate Guide to Qualitative Research - Part 1: The Basics

research results bias

  • Introduction and overview
  • What is qualitative research?
  • What is qualitative data?
  • Examples of qualitative data
  • Qualitative vs. quantitative research
  • Mixed methods
  • Qualitative research preparation
  • Theoretical perspective
  • Theoretical framework
  • Literature reviews
  • Research question
  • Conceptual framework
  • Conceptual vs. theoretical framework
  • Data collection
  • Qualitative research methods
  • Focus groups
  • Observational research
  • Case studies
  • Ethnographical research
  • Ethical considerations
  • Confidentiality and privacy

What is research bias?

Understanding unconscious bias, how to avoid bias in research, bias and subjectivity in research.

  • Power dynamics
  • Reflexivity

Bias in research

In a purely objective world, research bias would not exist because knowledge would be a fixed and unmovable resource; either one knows about a particular concept or phenomenon, or they don't. However, qualitative research and the social sciences both acknowledge that subjectivity and bias exist in every aspect of the social world, which naturally includes the research process too. This bias is manifest in the many different ways that knowledge is understood, constructed, and negotiated, both in and out of research.

research results bias

Understanding research bias has profound implications for data collection methods and data analysis , requiring researchers to take particular care of how to account for the insights generated from their data .

Research bias, often unavoidable, is a systematic error that can creep into any stage of the research process , skewing our understanding and interpretation of findings. From data collection to analysis, interpretation , and even publication , bias can distort the truth we seek to capture and communicate in our research.

It’s also important to distinguish between bias and subjectivity, especially when engaging in qualitative research . Most qualitative methodologies are based on epistemological and ontological assumptions that there is no such thing as a fixed or objective world that exists “out there” that can be empirically measured and understood through research. Rather, many qualitative researchers embrace the socially constructed nature of our reality and thus recognize that all data is produced within a particular context by participants with their own perspectives and interpretations. Moreover, the researcher’s own subjective experiences inevitably shape how they make sense of the data. These subjectivities are considered to be strengths, not limitations, of qualitative research approaches, because they open new avenues for knowledge generation. This is also why reflexivity is so important in qualitative research. When we refer to bias in this guide, on the other hand, we are referring to systematic errors that can negatively affect the research process but that can be mitigated through researchers’ careful efforts.

To fully grasp what research bias is, it's essential to understand the dual nature of bias. Bias is not inherently evil. It's simply a tendency, inclination, or prejudice for or against something. In our daily lives, we're subject to countless biases, many of which are unconscious. They help us navigate our world, make quick decisions, and understand complex situations. But when conducting research, these same biases can cause significant issues.

research results bias

Research bias can affect the validity and credibility of research findings, leading to erroneous conclusions. It can emerge from the researcher's subconscious preferences or the methodological design of the study itself. For instance, if a researcher unconsciously favors a particular outcome of the study, this preference could affect how they interpret the results, leading to a type of bias known as confirmation bias.

Research bias can also arise due to the characteristics of study participants. If the researcher selectively recruits participants who are more likely to produce desired outcomes, this can result in selection bias.

Another form of bias can stem from data collection methods . If a survey question is phrased in a way that encourages a particular response, this can introduce response bias. Moreover, inappropriate survey questions can have a detrimental effect on future research if such studies are seen by the general population as biased toward particular outcomes depending on the preferences of the researcher.

Bias can also occur during data analysis . In qualitative research for instance, the researcher's preconceived notions and expectations can influence how they interpret and code qualitative data, a type of bias known as interpretation bias. It's also important to note that quantitative research is not free of bias either, as sampling bias and measurement bias can threaten the validity of any research findings.

Given these examples, it's clear that research bias is a complex issue that can take many forms and emerge at any stage in the research process. This section will delve deeper into specific types of research bias, provide examples, discuss why it's an issue, and provide strategies for identifying and mitigating bias in research.

What is an example of bias in research?

Bias can appear in numerous ways. One example is confirmation bias, where the researcher has a preconceived explanation for what is going on in their data, and any disconfirming evidence is (unconsciously) ignored. For instance, a researcher conducting a study on daily exercise habits might be inclined to conclude that meditation practices lead to greater engagement in exercise because that researcher has personally experienced these benefits. However, conducting rigorous research entails assessing all the data systematically and verifying one’s conclusions by checking for both supporting and refuting evidence.

research results bias

What is a common bias in research?

Confirmation bias is one of the most common forms of bias in research. It happens when researchers unconsciously focus on data that supports their ideas while ignoring or undervaluing data that contradicts their ideas. This bias can lead researchers to mistakenly confirm their theories, despite having insufficient or conflicting evidence.

What are the different types of bias?

There are several types of research bias, each presenting unique challenges. Some common types include:

Confirmation bias: As already mentioned, this happens when a researcher focuses on evidence supporting their theory while overlooking contradictory evidence.

Selection bias: This occurs when the researcher's method of choosing participants skews the sample in a particular direction.

Response bias: This happens when participants in a study respond inaccurately or falsely, often due to misleading or poorly worded questions.

Observer bias (or researcher bias): This occurs when the researcher unintentionally influences the results because of their expectations or preferences.

Publication bias: This type of bias arises when studies with positive results are more likely to get published, while studies with negative or null results are often ignored.

Analysis bias: This type of bias occurs when the data is manipulated or analyzed in a way that leads to a particular result, whether intentionally or unintentionally.

research results bias

What is an example of researcher bias?

Researcher bias, also known as observer bias, can occur when a researcher's expectations or personal beliefs influence the results of a study. For instance, if a researcher believes that a particular therapy is effective, they might unconsciously interpret ambiguous results in a way that supports the efficacy of the therapy, even if the evidence is not strong enough.

Even quantitative research methodologies are not immune from bias from researchers. Market research surveys or clinical trial research, for example, may encounter bias when the researcher chooses a particular population or methodology to achieve a specific research outcome. Questions in customer feedback surveys whose data is employed in quantitative analysis can be structured in such a way as to bias survey respondents toward certain desired answers.

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Identifying and avoiding bias in research

As we will remind you throughout this chapter, bias is not a phenomenon that can be removed altogether, nor should we think of it as something that should be eliminated. In a subjective world involving humans as researchers and research participants, bias is unavoidable and almost necessary for understanding social behavior. The section on reflexivity later in this guide will highlight how different perspectives among researchers and human subjects are addressed in qualitative research. That said, bias in excess can place the credibility of a study's findings into serious question. Scholars who read your research need to know what new knowledge you are generating, how it was generated, and why the knowledge you present should be considered persuasive. With that in mind, let's look at how bias can be identified and, where it interferes with research, minimized.

How do you identify bias in research?

Identifying bias involves a critical examination of your entire research study involving the formulation of the research question and hypothesis , the selection of study participants, the methods for data collection, and the analysis and interpretation of data. Researchers need to assess whether each stage has been influenced by bias that may have skewed the results. Tools such as bias checklists or guidelines, peer review , and reflexivity (reflecting on one's own biases) can be instrumental in identifying bias.

How do you identify research bias?

Identifying research bias often involves careful scrutiny of the research methodology and the researcher's interpretations. Was the sample of participants relevant to the research question ? Were the interview or survey questions leading? Were there any conflicts of interest that could have influenced the results? It also requires an understanding of the different types of bias and how they might manifest in a research context. Does the bias occur in the data collection process or when the researcher is analyzing data?

Research transparency requires a careful accounting of how the study was designed, conducted, and analyzed. In qualitative research involving human subjects, the researcher is responsible for documenting the characteristics of the research population and research context. With respect to research methods, the procedures and instruments used to collect and analyze data are described in as much detail as possible.

While describing study methodologies and research participants in painstaking detail may sound cumbersome, a clear and detailed description of the research design is necessary for good research. Without this level of detail, it is difficult for your research audience to identify whether bias exists, where bias occurs, and to what extent it may threaten the credibility of your findings.

How to recognize bias in a study?

Recognizing bias in a study requires a critical approach. The researcher should question every step of the research process: Was the sample of participants selected with care? Did the data collection methods encourage open and sincere responses? Did personal beliefs or expectations influence the interpretation of the results? External peer reviews can also be helpful in recognizing bias, as others might spot potential issues that the original researcher missed.

The subsequent sections of this chapter will delve into the impacts of research bias and strategies to avoid it. Through these discussions, researchers will be better equipped to handle bias in their work and contribute to building more credible knowledge.

Unconscious biases, also known as implicit biases, are attitudes or stereotypes that influence our understanding, actions, and decisions in an unconscious manner. These biases can inadvertently infiltrate the research process, skewing the results and conclusions. This section aims to delve deeper into understanding unconscious bias, its impact on research, and strategies to mitigate it.

What is unconscious bias?

Unconscious bias refers to prejudices or social stereotypes about certain groups that individuals form outside their conscious awareness. Everyone holds unconscious beliefs about various social and identity groups, and these biases stem from a tendency to organize social worlds into categories.

research results bias

How does unconscious bias infiltrate research?

Unconscious bias can infiltrate research in several ways. It can affect how researchers formulate their research questions or hypotheses , how they interact with participants, their data collection methods, and how they interpret their data . For instance, a researcher might unknowingly favor participants who share similar characteristics with them, which could lead to biased results.

Implications of unconscious bias

The implications of unconscious research bias are far-reaching. It can compromise the validity of research findings , influence the choice of research topics, and affect peer review processes . Unconscious bias can also lead to a lack of diversity in research, which can severely limit the value and impact of the findings.

Strategies to mitigate unconscious research bias

While it's challenging to completely eliminate unconscious bias, several strategies can help mitigate its impact. These include being aware of potential unconscious biases, practicing reflexivity , seeking diverse perspectives for your study, and engaging in regular bias-checking activities, such as bias training and peer debriefing .

By understanding and acknowledging unconscious bias, researchers can take steps to limit its impact on their work, leading to more robust findings.

Why is researcher bias an issue?

Research bias is a pervasive issue that researchers must diligently consider and address. It can significantly impact the credibility of findings. Here, we break down the ramifications of bias into two key areas.

How bias affects validity

Research validity refers to the accuracy of the study findings, or the coherence between the researcher’s findings and the participants’ actual experiences. When bias sneaks into a study, it can distort findings and move them further away from the realities that were shared by the research participants. For example, if a researcher's personal beliefs influence their interpretation of data , the resulting conclusions may not reflect what the data show or what participants experienced.

The transferability problem

Transferability is the extent to which your study's findings can be applied beyond the specific context or sample studied. Applying knowledge from one context to a different context is how we can progress and make informed decisions. In quantitative research , the generalizability of a study is a key component that shapes the potential impact of the findings. In qualitative research , all data and knowledge that is produced is understood to be embedded within a particular context, so the notion of generalizability takes on a slightly different meaning. Rather than assuming that the study participants are statistically representative of the entire population, qualitative researchers can reflect on which aspects of their research context bear the most weight on their findings and how these findings may be transferable to other contexts that share key similarities.

How does bias affect research?

Research bias, if not identified and mitigated, can significantly impact research outcomes. The ripple effects of research bias extend beyond individual studies, impacting the body of knowledge in a field and influencing policy and practice. Here, we delve into three specific ways bias can affect research.

Distortion of research results

Bias can lead to a distortion of your study's findings. For instance, confirmation bias can cause a researcher to focus on data that supports their interpretation while disregarding data that contradicts it. This can skew the results and create a misleading picture of the phenomenon under study.

Undermining scientific progress

When research is influenced by bias, it not only misrepresents participants’ realities but can also impede scientific progress. Biased studies can lead researchers down the wrong path, resulting in wasted resources and efforts. Moreover, it could contribute to a body of literature that is skewed or inaccurate, misleading future research and theories.

Influencing policy and practice based on flawed findings

Research often informs policy and practice. If the research is biased, it can lead to the creation of policies or practices that are ineffective or even harmful. For example, a study with selection bias might conclude that a certain intervention is effective, leading to its broad implementation. However, suppose the transferability of the study's findings was not carefully considered. In that case, it may be risky to assume that the intervention will work as well in different populations, which could lead to ineffective or inequitable outcomes.

research results bias

While it's almost impossible to eliminate bias in research entirely, it's crucial to mitigate its impact as much as possible. By employing thoughtful strategies at every stage of research, we can strive towards rigor and transparency , enhancing the quality of our findings. This section will delve into specific strategies for avoiding bias.

How do you know if your research is biased?

Determining whether your research is biased involves a careful review of your research design, data collection , analysis , and interpretation . It might require you to reflect critically on your own biases and expectations and how these might have influenced your research. External peer reviews can also be instrumental in spotting potential bias.

Strategies to mitigate bias

Minimizing bias involves careful planning and execution at all stages of a research study. These strategies could include formulating clear, unbiased research questions , ensuring that your sample meaningfully represents the research problem you are studying, crafting unbiased data collection instruments, and employing systematic data analysis techniques. Transparency and reflexivity throughout the process can also help minimize bias.

Mitigating bias in data collection

To mitigate bias in data collection, ensure your questions are clear, neutral, and not leading. Triangulation, or using multiple methods or data sources, can also help to reduce bias and increase the credibility of your findings.

Mitigating bias in data analysis

During data analysis , maintaining a high level of rigor is crucial. This might involve using systematic coding schemes in qualitative research or appropriate statistical tests in quantitative research . Regularly questioning your interpretations and considering alternative explanations can help reduce bias. Peer debriefing , where you discuss your analysis and interpretations with colleagues, can also be a valuable strategy.

By using these strategies, researchers can significantly reduce the impact of bias on their research, enhancing the quality and credibility of their findings and contributing to a more robust and meaningful body of knowledge.

Impact of cultural bias in research

Cultural bias is the tendency to interpret and judge phenomena by standards inherent to one's own culture. Given the increasingly multicultural and global nature of research, understanding and addressing cultural bias is paramount. This section will explore the concept of cultural bias, its impacts on research, and strategies to mitigate it.

What is cultural bias in research?

Cultural bias refers to the potential for a researcher's cultural background, experiences, and values to influence the research process and findings. This can occur consciously or unconsciously and can lead to misinterpretation of data, unfair representation of cultures, and biased conclusions.

How does cultural bias infiltrate research?

Cultural bias can infiltrate research at various stages. It can affect the framing of research questions , the design of the study, the methods of data collection , and the interpretation of results . For instance, a researcher might unintentionally design a study that does not consider the cultural context of the participants, leading to a biased understanding of the phenomenon being studied.

Implications of cultural bias

The implications of cultural bias are profound. Cultural bias can skew your findings, limit the transferability of results, and contribute to cultural misunderstandings and stereotypes. This can ultimately lead to inaccurate or ethnocentric conclusions, further perpetuating cultural bias and inequities.

As a result, many social science fields like sociology and anthropology have been critiqued for cultural biases in research. Some of the earliest research inquiries in anthropology, for example, have had the potential to reduce entire cultures to simplistic stereotypes when compared to mainstream norms. A contemporary researcher respecting ethical and cultural boundaries, on the other hand, should seek to properly place their understanding of social and cultural practices in sufficient context without inappropriately characterizing them.

Strategies to mitigate cultural bias

Mitigating cultural bias requires a concerted effort throughout the research study. These efforts could include educating oneself about other cultures, being aware of one's own cultural biases, incorporating culturally diverse perspectives into the research process, and being sensitive and respectful of cultural differences. It might also involve including team members with diverse cultural backgrounds or seeking external cultural consultants to challenge assumptions and provide alternative perspectives.

By acknowledging and addressing cultural bias, researchers can contribute to more culturally competent, equitable, and valid research. This not only enriches the scientific body of knowledge but also promotes cultural understanding and respect.

research results bias

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Keep in mind that bias is a force to be mitigated, not a phenomenon that can be eliminated altogether, and the subjectivities of each person are what make our world so complex and interesting. As things are continuously changing and adapting, research knowledge is also continuously being updated as we further develop our understanding of the world around us.

research results bias

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Incorporate STEM journalism in your classroom

  • Exercise type: Activity
  • Topic: Science & Society
  • Category: Research & Design
  • Category: Diversity in STEM

How bias affects scientific research

  • Download Student Worksheet

Purpose: Students will work in groups to evaluate bias in scientific research and engineering projects and to develop guidelines for minimizing potential biases.

Procedural overview: After reading the Science News for Students article “ Think you’re not biased? Think again ,” students will discuss types of bias in scientific research and how to identify it. Students will then search the Science News archive for examples of different types of bias in scientific and medical research. Students will read the National Institute of Health’s Policy on Sex as a Biological Variable and analyze how this policy works to reduce bias in scientific research on the basis of sex and gender. Based on their exploration of bias, students will discuss the benefits and limitations of research guidelines for minimizing particular types of bias and develop guidelines of their own.

Approximate class time: 2 class periods

How Bias Affects Scientific Research student guide

Computer with access to the Science News archive

Interactive meeting and screen-sharing application for virtual learning (optional)

Directions for teachers:

One of the guiding principles of scientific inquiry is objectivity. Objectivity is the idea that scientific questions, methods and results should not be affected by the personal values, interests or perspectives of researchers. However, science is a human endeavor, and experimental design and analysis of information are products of human thought processes. As a result, biases may be inadvertently introduced into scientific processes or conclusions.

In scientific circles, bias is described as any systematic deviation between the results of a study and the “truth.” Bias is sometimes described as a tendency to prefer one thing over another, or to favor one person, thing or explanation in a way that prevents objectivity or that influences the outcome of a study or the understanding of a phenomenon. Bias can be introduced in multiple points during scientific research — in the framing of the scientific question, in the experimental design, in the development or implementation of processes used to conduct the research, during collection or analysis of data, or during the reporting of conclusions.

Researchers generally recognize several different sources of bias, each of which can strongly affect the results of STEM research. Three types of bias that often occur in scientific and medical studies are researcher bias, selection bias and information bias.

Researcher bias occurs when the researcher conducting the study is in favor of a certain result. Researchers can influence outcomes through their study design choices, including who they choose to include in a study and how data are interpreted. Selection bias can be described as an experimental error that occurs when the subjects of the study do not accurately reflect the population to whom the results of the study will be applied. This commonly happens as unequal inclusion of subjects of different races, sexes or genders, ages or abilities. Information bias occurs as a result of systematic errors during the collection, recording or analysis of data.

When bias occurs, a study’s results may not accurately represent phenomena in the real world, or the results may not apply in all situations or equally for all populations. For example, if a research study does not address the full diversity of people to whom the solution will be applied, then the researchers may have missed vital information about whether and how that solution will work for a large percentage of a target population.

Bias can also affect the development of engineering solutions. For example, a new technology product tested only with teenagers or young adults who are comfortable using new technologies may have user experience issues when placed in the hands of older adults or young children.

Want to make it a virtual lesson? Post the links to the  Science News for Students article “ Think you’re not biased? Think again ,” and the National Institutes of Health information on sickle-cell disease . A link to additional resources can be provided for the students who want to know more. After students have reviewed the information at home, discuss the four questions in the setup and the sickle-cell research scenario as a class. When the students have a general understanding of bias in research, assign students to breakout rooms to look for examples of different types of bias in scientific and medical research, to discuss the Science News article “ Biomedical studies are including more female subjects (finally) ” and the National Institute of Health’s Policy on Sex as a Biological Variable and to develop bias guidelines of their own. Make sure the students have links to all articles they will need to complete their work. Bring the groups back together for an all-class discussion of the bias guidelines they write.

Assign the Science News for Students article “ Think you’re not biased? Think again ” as homework reading to introduce students to the core concepts of scientific objectivity and bias. Request that they answer the first two questions on their guide before the first class discussion on this topic. In this discussion, you will cover the idea of objective truth and introduce students to the terminology used to describe bias. Use the background information to decide what level of detail you want to give to your students.

As students discuss bias, help them understand objective and subjective data and discuss the importance of gathering both kinds of data. Explain to them how these data differ. Some phenomena — for example, body temperature, blood type and heart rate — can be objectively measured. These data tend to be quantitative. Other phenomena cannot be measured objectively and must be considered subjectively. Subjective data are based on perceptions, feelings or observations and tend to be qualitative rather than quantitative. Subjective measurements are common and essential in biomedical research, as they can help researchers understand whether a therapy changes a patient’s experience. For instance, subjective data about the amount of pain a patient feels before and after taking a medication can help scientists understand whether and how the drug works to alleviate pain. Subjective data can still be collected and analyzed in ways that attempt to minimize bias.

Try to guide student discussion to include a larger context for bias by discussing the effects of bias on understanding of an “objective truth.” How can someone’s personal views and values affect how they analyze information or interpret a situation?

To help students understand potential effects of biases, present them with the following scenario based on information from the National Institutes of Health :

Sickle-cell disease is a group of inherited disorders that cause abnormalities in red blood cells. Most of the people who have sickle-cell disease are of African descent; it also appears in populations from the Mediterranean, India and parts of Latin America. Males and females are equally likely to inherit the condition. Imagine that a therapy was developed to treat the condition, and clinical trials enlisted only male subjects of African descent. How accurately would the results of that study reflect the therapy’s effectiveness for all people who suffer from sickle-cell disease?

In the sickle-cell scenario described above, scientists will have a good idea of how the therapy works for males of African descent. But they may not be able to accurately predict how the therapy will affect female patients or patients of different races or ethnicities. Ask the students to consider how they would devise a study that addressed all the populations affected by this disease.

Before students move on, have them answer the following questions. The first two should be answered for homework and discussed in class along with the remaining questions.

1.What is bias?

In common terms, bias is a preference for or against one idea, thing or person. In scientific research, bias is a systematic deviation between observations or interpretations of data and an accurate description of a phenomenon.

2. How can biases affect the accuracy of scientific understanding of a phenomenon? How can biases affect how those results are applied?

Bias can cause the results of a scientific study to be disproportionately weighted in favor of one result or group of subjects. This can cause misunderstandings of natural processes that may make conclusions drawn from the data unreliable. Biased procedures, data collection or data interpretation can affect the conclusions scientists draw from a study and the application of those results. For example, if the subjects that participate in a study testing an engineering design do not reflect the diversity of a population, the end product may not work as well as desired for all users.

3. Describe two potential sources of bias in a scientific, medical or engineering research project. Try to give specific examples.

Researchers can intentionally or unintentionally introduce biases as a result of their attitudes toward the study or its purpose or toward the subjects or a group of subjects. Bias can also be introduced by methods of measuring, collecting or reporting data. Examples of potential sources of bias include testing a small sample of subjects, testing a group of subjects that is not diverse and looking for patterns in data to confirm ideas or opinions already held.

4. How can potential biases be identified and eliminated before, during or after a scientific study?

Students should brainstorm ways to identify sources of bias in the design of research studies. They may suggest conducting implicit bias testing or interviews before a study can be started, developing guidelines for research projects, peer review of procedures and samples/subjects before beginning a study, and peer review of data and conclusions after the study is completed and before it is published. Students may focus on the ideals of transparency and replicability of results to help reduce biases in scientific research.

Obtain and evaluate information about bias

Students will now work in small groups to select and analyze articles for different types of bias in scientific and medical research. Students will start by searching the Science News or Science News for Students archives and selecting articles that describe scientific studies or engineering design projects. If the Science News or Science News for Students articles chosen by students do not specifically cite and describe a study, students should consult the Citations at the end of the article for links to related primary research papers. Students may need to read the methods section and the conclusions of the primary research paper to better understand the project’s design and to identify potential biases. Do not assume that every scientific paper features biased research.

Student groups should evaluate the study or engineering design project outlined in the article to identify any biases in the experimental design, data collection, analysis or results. Students may need additional guidance for identifying biases. Remind them of the prior discussion about sources of bias and task them to review information about indicators of bias. Possible indicators include extreme language such as all , none or nothing ; emotional appeals rather than logical arguments; proportions of study subjects with specific characteristics such as gender, race or age; arguments that support or refute one position over another and oversimplifications or overgeneralizations. Students may also want to look for clues related to the researchers’ personal identity such as race, religion or gender. Information on political or religious points of view, sources of funding or professional affiliations may also suggest biases.

Students should also identify any deliberate attempts to reduce or eliminate bias in the project or its results. Then groups should come back together and share the results of their analysis with the class.

If students need support in searching the archives for appropriate articles, encourage groups to brainstorm search terms that may turn up related articles. Some potential search terms include bias , study , studies , experiment , engineer , new device , design , gender , sex , race , age , aging , young , old , weight , patients , survival or medical .

If you are short on time or students do not have access to the Science News or Science News for Students archive, you may want to provide articles for students to review. Some suggested articles are listed in the additional resources  below.

Once groups have selected their articles, students should answer the following questions in their groups.

1. Record the title and URL of the article and write a brief summary of the study or project.

Answers will vary, but students should accurately cite the article evaluated and summarize the study or project described in the article. Sample answer: We reviewed the Science News article “Even brain images can be biased,” which can be found at www.sciencenews.org/blog/scicurious/even-brain-images-can-be-biased. This article describes how scientific studies of human brains that involve electronic images of brains tend to include study subjects from wealthier and more highly educated households and how researchers set out to collect new data to make the database of brain images more diverse.

2. What sources of potential bias (if any) did you identify in the study or project? Describe any procedures or policies deliberately included in the study or project to eliminate biases.

The article “Even brain images can be biased” describes how scientists identified a sampling bias in studies of brain images that resulted from the way subjects were recruited. Most of these studies were conducted at universities, so many college students volunteer to participate, which resulted in the samples being skewed toward wealthier, educated, white subjects. Scientists identified a database of pediatric brain images and evaluated the diversity of the subjects in that database. They found that although the subjects in that database were more ethnically diverse than the U.S. population, the subjects were generally from wealthier households and the parents of the subjects tended to be more highly educated than average. Scientists applied statistical methods to weight the data so that study samples from the database would more accurately reflect American demographics.

3. How could any potential biases in the study or design project have affected the results or application of the results to the target population?

Scientists studying the rate of brain development in children were able to recognize the sampling bias in the brain image database. When scientists were able to apply statistical methods to ensure a better representation of socioeconomically diverse samples, they saw a different pattern in the rate of brain development in children. Scientists learned that, in general, children’s brains matured more quickly than they had previously thought. They were able to draw new conclusions about how certain factors, such as family wealth and education, affected the rate at which children’s brains developed. But the scientsits also suggested that they needed to perform additional studies with a deliberately selected group of children to ensure true diversity in the samples.

In this phase, students will review the Science News article “ Biomedical studies are including more female subjects (finally) ” and the NIH Policy on Sex as a Biological Variable , including the “ guidance document .” Students will identify how sex and gender biases may have affected the results of biomedical research before NIH instituted its policy. The students will then work with their group to recommend other policies to minimize biases in biomedical research.

To guide their development of proposed guidelines, students should answer the following questions in their groups.

1. How have sex and gender biases affected the value and application of biomedical research?

Gender and sex biases in biomedical research have diminished the accuracy and quality of research studies and reduced the applicability of results to the entire population. When girls and women are not included in research studies, the responses and therapeutic outcomes of approximately half of the target population for potential therapies remain unknown.

2. Why do you think the NIH created its policy to reduce sex and gender biases?

In the guidance document, the NIH states that “There is a growing recognition that the quality and generalizability of biomedical research depends on the consideration of key biological variables, such as sex.” The document goes on to state that many diseases and conditions affect people of both sexes, and restricting diversity of biological variables, notably sex and gender, undermines the “rigor, transparency, and generalizability of research findings.”

3. What impact has the NIH Policy on Sex as a Biological Variable had on biomedical research?

The NIH’s policy that sex is factored into research designs, analyses and reporting tries to ensure that when developing and funding biomedical research studies, researchers and institutes address potential biases in the planning stages, which helps to reduce or eliminate those biases in the final study. Including females in biomedical research studies helps to ensure that the results of biomedical research are applicable to a larger proportion of the population, expands the therapies available to girls and women and improves their health care outcomes.

4. What other policies do you think the NIH could institute to reduce biases in biomedical research? If you were to recommend one set of additional guidelines for reducing bias in biomedical research, what guidelines would you propose? Why?

Students could suggest that the NIH should have similar policies related to race, gender identity, wealth/economic status and age. Students should identify a category of bias or an underserved segment of the population that they think needs to be addressed in order to improve biomedical research and health outcomes for all people and should recommend guidelines to reduce bias related to that group. Students recommending guidelines related to race might suggest that some populations, such as African Americans, are historically underserved in terms of access to medical services and health care, and they might suggest guidelines to help reduce the disparity. Students might recommend that a certain percentage of each biomedical research project’s sample include patients of diverse racial and ethnic backgrounds.

5. What biases would your suggested policy help eliminate? How would it accomplish that goal?

Students should describe how their proposed policy would address a discrepancy in the application of biomedical research to the entire human population. Race can be considered a biological variable, like sex, and race has been connected to higher or lower incidence of certain characteristics or medical conditions, such as blood types or diabetes, which sometimes affect how the body reponds to infectious agents, drugs, procedures or other therapies. By ensuring that people from diverse racial and ethnic groups are included in biomedical research studies, scientists and medical professionals can provide better medical care to members of those populations.

Class discussion about bias guidelines

Allow each group time to present its proposed bias-reducing guideline to another group and to receive feedback. Then provide groups with time to revise their guidelines, if necessary. Act as a facilitator while students conduct the class discussion. Use this time to assess individual and group progress. Students should demonstrate an understanding of different biases that may affect patient outcomes in biomedical research studies and in practical medical settings. As part of the group discussion, have students answer the following questions.

1. Why is it important to identify and eliminate biases in research and engineering design?

The goal of most scientific research and engineering projects is to improve the quality of life and the depth of understanding of the world we live in. By eliminating biases, we can better serve the entirety of the human population and the planet .

2. Were there any guidelines that were suggested by multiple groups? How do those actions or policies help reduce bias?

Answers will depend on the guidelines developed and recommended by other groups. Groups could suggest policies related to race, gender identity, wealth/economic status and age. Each group should clearly identify how its guidelines are designed to reduce bias and improve the quality of human life.

3. Which guidelines developed by your classmates do you think would most reduce the effects of bias on research results or engineering designs? Support your selection with evidence and scientific reasoning.

Answers will depend on the guidelines developed and recommended by other groups. Students should agree that guidelines that minimize inequities and improve health care outcomes for a larger group are preferred. Guidelines addressing inequities of race and wealth/economic status are likely to expand access to improved medical care for the largest percentage of the population. People who grow up in less economically advantaged settings have specific health issues related to nutrition and their access to clean water, for instance. Ensuring that people from the lowest economic brackets are represented in biomedical research improves their access to medical care and can dramatically change the length and quality of their lives.

Possible extension

Challenge students to honestly evaluate any biases they may have. Encourage them to take an Implicit Association Test (IAT) to identify any implicit biases they may not recognize. Harvard University has an online IAT platform where students can participate in different assessments to identify preferences and biases related to sex and gender, race, religion, age, weight and other factors. You may want to challenge students to take a test before they begin the activity, and then assign students to take a test after completing the activity to see if their preferences have changed. Students can report their results to the class if they want to discuss how awareness affects the expression of bias.

Additional resources

If you want additional resources for the discussion or to provide resources for student groups, check out the links below.

Additional Science News articles:

Even brain images can be biased

Data-driven crime prediction fails to erase human bias

What we can learn from how a doctor’s race can affect Black newborns’ survival

Bias in a common health care algorithm disproportionately hurts black patients

Female rats face sex bias too

There’s no evidence that a single ‘gay gene’ exists

Positive attitudes about aging may pay off in better health

What male bias in the mammoth fossil record says about the animal’s social groups

The man flu struggle might be real, says one researcher

Scientists may work to prevent bias, but they don’t always say so

The Bias Finders

Showdown at Sex Gap

University resources:

Project Implicit (Take an Implicit Association Tests)

Catalogue of Bias

Understanding Health Research

  • Research Bias: Definition, Types + Examples

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Sometimes, in the cause of carrying out a systematic investigation, the researcher may influence the process intentionally or unknowingly. When this happens, it is termed as research bias, and like every other type of bias , it can alter your findings. 

Research bias is one of the dominant reasons for the poor validity of research outcomes. There are no hard and fast rules when it comes to research bias and this simply means that it can happen at any time; if you do not pay adequate attention. 

The spontaneity of research bias means you must take care to understand what it is, be able to identify its feature, and ultimately avoid or reduce its occurrence to the barest minimum. In this article, we will show you how to handle bias in research and how to create unbiased research surveys with Formplus. 

What is Research Bias? 

Research bias happens when the researcher skews the entire process towards a specific research outcome by introducing a systematic error into the sample data. In other words, it is a process where the researcher influences the systematic investigation to arrive at certain outcomes. 

When any form of bias is introduced in research, it takes the investigation off-course and deviates it from its true outcomes. Research bias can also happen when the personal choices and preferences of the researcher have undue influence on the study. 

For instance, let’s say a religious conservative researcher is conducting a study on the effects of alcohol. If the researcher’s conservative beliefs prompt him or her to create a biased survey or have sampling bias , then this is a case of research bias. 

Types of Research Bias 

  • Design Bias

Design bias has to do with the structure and methods of your research. It happens when the research design, survey questions, and research method is largely influenced by the preferences of the researcher rather than what works best for the research context. 

In many instances, poor research design or a pack of synergy between the different contributing variables in your systematic investigation can infuse bias into your research process. Research bias also happens when the personal experiences of the researcher influence the choice of the research question and methodology. 

Example of Design Bias  

A researcher who is involved in the manufacturing process of a new drug may design a survey with questions that only emphasize the strengths and value of the drug in question. 

  • Selection or Participant Bias

Selection bias happens when the research criteria and study inclusion method automatically exclude some part of your population from the research process. When you choose research participants that exhibit similar characteristics, you’re more likely to arrive at study outcomes that are uni-dimensional. 

Selection bias manifests itself in different ways in the context of research. Inclusion bias is particularly popular in quantitative research and it happens when you select participants to represent your research population while ignoring groups that have alternative experiences. 

Examples of Selection Bias  

  • Administering your survey online; thereby limiting it to internet savvy individuals and excluding members of your population without internet access. 
  • Collecting data about parenting from a mother’s group. The findings in this type of research will be biased towards mothers while excluding the experiences of the fathers. 
  • Publication Bias

Peer-reviewed journals and other published academic papers, in many cases, have some degree of bias. This bias is often imposed on them by the publication criteria for research papers in a particular field. Researchers work their papers to meet these criteria and may ignore information or methods that are not in line with them. 

For example, research papers in quantitative research are more likely to be published if they contain statistical information. On the other hand, Non-publication in qualitative studies is more likely to occur because of a lack of depth when describing study methodologies and findings are not presented. 

  • Analysis Bias

This is a type of research bias that creeps in during data processing. Many times, when sorting and analyzing data, the researcher may focus on data samples that confirm his or her thoughts, expectations, or personal experiences; that is, data that favors the research hypothesis. 

This means that the researcher, albeit deliberately or unintentionally, ignores data samples that are inconsistent and suggest research outcomes that differ from the hypothesis. Analysis bias can be far-reaching because it alters the research outcomes significantly and provides a false presentation of what is obtainable in the research environment. 

Example of Analysis Bias  

While researching cannabis, a researcher pays attention to data samples that reinforce the negative effects of cannabis while ignoring data that suggests positives.

  • Data Collection Bias

Data collection bias is also known as measurement bias and it happens when the researcher’s personal preferences or beliefs affect how data samples are gathered in the systematic investigation. Data collection bias happens in both q ualitative and quantitative research methods. 

In quantitative research, data collection methods can occur when you use a data-gathering tool or method that is not suitable for your research population. For example, asking individuals who do not have access to the internet, to complete a survey via email or your website. 

In qualitative research, data collection bias happens when you ask bad survey questions during a semi-structured or unstructured interview . Bad survey questions are questions that nudge the interviewee towards implied assumptions. Leading and loaded questions are common examples of bad survey questions. 

  • Procedural Bias

Procedural is a type of research bias that happens when the participants in a study are not given enough time to complete surveys. The result is that respondents end up providing half-thoughts and incomplete information that does not provide a true representation of their thoughts. 

There are different ways to subject respondents to procedural respondents. For instance, asking respondents to complete a survey quickly to access an incentive, may force them to fill in false information to simply get things over with. 

Example of Procedural Bias

  • Asking employees to complete an employee feedback survey during break time. This timeframe puts respondents under undue pressure and can affect the validity of their responses.  

Bias in Quantitative Research

In quantitative research, the researcher often tries to deny the existence of any bias, by eliminating any type of bias in the systematic investigation. Sampling bias is one of the most types of quantitative research biases and it is concerned with the samples you omit and/or include in your study. 

Types of Quantitative Research Bias

Design bias occurs in quantitative research when the research methods or processes alter the outcomes or findings of a systematic investigation. It can occur when the experiment is being conducted or during the analysis of the data to arrive at a valid conclusion. 

Many times, design biases result from the failure of the researchers to take into account the likely impact of the bias in the research they conduct. This makes the researcher ignore the needs of the research context and instead, prioritize his or her preferences. 

  • Sampling Bias

Sampling bias in quantitative research occurs when some members of the research population are systematically excluded from the data sample during research. It also means that some groups in the research population are more likely to be selected in a sample than the others. 

Sampling bias in quantitative research mainly occurs in systematic and random sampling. For example, a study about breast cancer that has just male participants can be said to have sampling bias since it excludes the female group in the research population. 

Bias in Qualitative Research

In qualitative research, the researcher accepts and acknowledges the bias without trying to deny its existence. This makes it easier for the researcher to clearly define the inherent biases and outline its possible implications while trying to minimize its effects. 

Qualitative research defines bias in terms of how valid and reliable the research results are. Bias in qualitative research distorts the research findings and also provides skewed data that defeats the validity and reliability of the systematic investigation. 

Types of Bias in Qualitative Research

  • Bias from Moderator

The interviewer or moderator in qualitative data collection can impose several biases on the process. The moderator can introduce bias in the research based on his or her disposition, expression, tone, appearance, idiolect, or relation with the research participants. 

  • Biased Questions

The framing and presentation of the questions during the research process can also lead to bias. Biased questions like leading questions , double- barrelled questions, negative questions, and loaded questions , can influence the way respondents provide answers and the authenticity of the responses they present. 

The researcher must identify and eliminate biased questions in qualitative research or rephrase them if they cannot be taken out altogether. Remember that questions form the main basis through which information is collected in research and so, biased questions can lead to invalid research findings. 

  • Biased Reporting

Biased reporting is yet another challenge in qualitative research. It happens when the research results are altered due to personal beliefs, customs, attitudes, culture, and errors among many other factors. It also means that the researcher must have analyzed the research data based on his/her beliefs rather than the views perceived by the respondents. 

Bias in Psychology

Cognitive biases can affect research and outcomes in psychology. For example, during a stop-and-search exercise, law enforcement agents may profile certain appearances and physical dispositions as law-abiding. Due to this cognitive bias, individuals who do not exhibit these outlined behaviors can be wrongly profiled as criminals. 

Another example of cognitive bias in psychology can be observed in the classroom. During a class assessment, an invigilator who is looking for physical signs of malpractice might mistakenly classify other behaviors as evidence of malpractice; even though this may not be the case. 

Bias in Market Research

There are 5 common biases in market research – social desirability bias, habituation bias, sponsor bias, confirmation bias, and cultural bias. Let’s find out more about them.

  • Social desirability bias happens when respondents fill in incorrect information in market research surveys because they want to be accepted or liked. It happens when respondents are seeking social approval and so, fail to communicate how they truly feel about the statement or question being considered. 

A good example will be market research to find out preferred sexual enhancement methods for adults. Some persons may not want to admit that they use sexual enhancement drugs to avoid criticism or disapproval.

  • Habituation bias happens when respondents give similar answers to questions that are structured in the same way. Lack of variety in survey questions can make respondents lose interest, become non-responsive, and simply regurgitate answers.  

For example, multiple-choice questions with the same set of answer options can cause habituation bias in your survey. What you get is that respondents just choose answer options without reflecting on how well their choices represent their thoughts, feelings, and ideas. 

  • Sponsor bias takes place when respondents have an idea of the brand or organization that is conducting the research. In this case, their perceptions, opinions, experiences, and feelings about the sponsor may influence how they answer the questions about that particular brand. 

For example, let’s say Formplus is carrying out a study to find out what the market’s preferred form builder is. Respondents may mention the sponsor for the survey (Formplus) as their preferred form builder out of obligation; especially when the survey has some incentives.

  • Confirmation bias happens when the overall research process is aimed at confirming the researcher’s perception or hypothesis about the research subjects. In other words, the research process is merely a formality to reinforce the researcher’s existing beliefs. 

Electoral polls often fall into the confirmation bias trap. For example, civil society organizations that are in support of one candidate can create a survey that paints the opposing candidate in a bad light to reinforce beliefs about their preferred candidate. 

  • Cultural bias arises from the assumptions we have about other cultures based on the values and standards we have for our own culture . For example, when asked to complete a survey about our culture, we may tilt towards positive answers. In the same vein, we are more likely to provide negative responses in a survey for a culture we do not like. 

How to Identify Bias in a Research

  • Pay attention to research design and methods. 
  • Observe the data collection process. Does it lean overwhelmingly towards a particular group in the survey population? 
  • Look out for bad survey questions like loaded questions and negative questions. 
  • Observe the data sample you have to confirm if it is a fair representation of your research population.

How to Avoid Research Bias 

  • Gather data from multiple sources: Be sure to collect data samples from the different groups in your research population. 
  • Verify your data: Before going ahead with the data analysis, try to check in with other data sources, and confirm if you are on the right track. 
  • If possible, ask research participants to help you review your findings: Ask the people who provided the data whether your interpretations seem to be representative of their beliefs. 
  • Check for alternative explanations: Try to identify and account for alternative reasons why you may have collected data samples the way you did. 
  • Ask other members of your team to review your results: Ask others to review your conclusions. This will help you see things that you missed or identify gaps in your argument that need to be addressed.

How to Create Unbiased Research Surveys with Formplus 

Formplus has different features that would help you create unbiased research surveys. Follow these easy steps to start creating your Formplus research survey today: 

  • Go to your Formplus dashboard and click on the “create new form” button. You can access the Formplus dashboard by signing into your Formplus account here. 

research results bias

  • After you click on the “create new form” button, you’d be taken to the form builder. This is where you can add different fields into your form and edit them accordingly. Formplus has over 30 form fields that you can simply drag and drop into your survey including rating fields and scales. 

logo-testing-survey-builder

  • After adding form fields and editing them, save your form to access the builder’s customization features. You can tweak the appearance of your form here by changing the form theme and adding preferred background images to it. 

research results bias

  • Copy the form link and share it with respondents. 

research results bias

Conclusion 

The first step to dealing with research bias is having a clear idea of what it is and also, being able to identify it in any form. In this article, we’ve shared important information about research bias that would help you identify it easily and work on minimizing its effects to the barest minimum. 

Formplus has many features and options that can help you deal with research bias as you create forms and questionnaires for quantitative and qualitative data collection. To take advantage of these, you can sign up for a Formplus account here. 

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Research bias: What it is, Types & Examples

Research bias is a technique where the researchers conducting the experiment modify the findings in order to present a specific consequence.

The researcher sometimes unintentionally or actively affects the process while executing a systematic inquiry. It is known as research bias, and it can affect your results just like any other sort of bias.

When it comes to studying bias, there are no hard and fast guidelines, which simply means that it can occur at any time. Experimental mistakes and a lack of concern for all relevant factors can lead to research bias.

One of the most common causes of study results with low credibility is study bias. Because of its informal nature, you must be cautious when characterizing bias in research. To reduce or prevent its occurrence, you need to be able to recognize its characteristics. 

This article will cover what it is, its type, and how to avoid it.

Content Index

What is research bias?

How does research bias affect the research process, types of research bias with examples, how questionpro helps in reducing bias in a research process.

Research bias is a technique in which the researchers conducting the experiment modify the findings to present a specific consequence. It is often known as experimenter bias.

Bias is a characteristic of the research technique that makes it rely on experience and judgment rather than data analysis. The most important thing to know about bias is that it is unavoidable in many fields. Understanding research bias and reducing the effects of biased views is an essential part of any research planning process.

For example, it is much easier to become attracted to a certain point of view when using social research subjects, compromising fairness.

Research bias can majorly affect the research process, weakening its integrity and leading to misleading or erroneous results. Here are some examples of how this bias might affect the research process:

Distorted research design

When bias is present, study results can be skewed or wrong. It can make the study less trustworthy and valid. If bias affects how a study is set up, how data is collected, or how it is analyzed, it can cause systematic mistakes that move the results away from the true or unbiased values.

Invalid conclusions

It can make it hard to believe that the findings of a study are correct. Biased research can lead to unjustified or wrong claims because the results may not reflect reality or give a complete picture of the research question.

Misleading interpretations

Bias can lead to inaccurate interpretations of research findings. It can alter the overall comprehension of the research issue. Researchers may be tempted to interpret the findings in a way that confirms their previous assumptions or expectations, ignoring alternate explanations or contradictory evidence.

Ethical concerns

This bias poses ethical considerations. It can have negative effects on individuals, groups, or society as a whole. Biased research can misinform decision-making processes, leading to ineffective interventions, policies, or therapies.

Damaged credibility

Research bias undermines scientific credibility. Biased research can damage public trust in science. It may reduce reliance on scientific evidence for decision-making.

Bias can be seen in practically every aspect of quantitative research and qualitative research , and it can come from both the survey developer and the participants. The sorts of biases that come directly from the survey maker are the easiest to deal with out of all the types of bias in research. Let’s look at some of the most typical research biases.

research results bias

Design bias

Design bias happens when a researcher fails to capture biased views in most experiments. It has something to do with the organization and its research methods. The researcher must demonstrate that they realize this and have tried to mitigate its influence.

Another design bias develops after the research is completed and the results are analyzed. It occurs when the researchers’ original concerns are not reflected in the exposure, which is all too often these days.

For example, a researcher working on a survey containing questions concerning health benefits may overlook the researcher’s awareness of the sample group’s limitations. It’s possible that the group tested was all male or all over a particular age.

Selection bias or sampling bias

Selection bias occurs when volunteers are chosen to represent your research population, but those with different experiences are ignored. 

In research, selection bias manifests itself in a variety of ways. When the sampling method puts preference into the research, this is known as sampling bias . Selection bias is also referred to as sampling bias.

For example, research on a disease that depended heavily on white male volunteers cannot be generalized to the full community, including women and people of other races or communities.

Procedural bias

Procedural bias is a sort of research bias that occurs when survey respondents are given insufficient time to complete surveys. As a result, participants are forced to submit half-thoughts with misinformation, which does not accurately reflect their thinking.

Another sort of study bias is using individuals who are forced to participate, as they are more likely to complete the survey fast, leaving them with enough time to accomplish other things.

For Example, If you ask your employees to survey their break, they may be pressured, which may compromise the validity of their results.

Publication or reporting bias

A sort of bias that influences research is publication bias. It is also known as reporting bias. It refers to a condition in which favorable outcomes are more likely to be reported than negative or empty ones. Analysis bias can also make it easier for reporting bias to happen.

The publication standards for research articles in a specific area frequently reflect this bias on them. Researchers sometimes choose not to disclose their outcomes if they believe the data do not reflect their theory.

As an example, there was seven research on the antidepressant drug Reboxetine. Among them, only one got published, and the others were unpublished.

Measurement of data collecting bias

A defect in the data collection process and measuring technique causes measurement bias. Data collecting bias is also known as measurement bias. It occurs in both qualitative and quantitative research methodologies. 

Data collection methods might occur in quantitative research when you use an approach that is not appropriate for your research population. Instrument bias is one of the most common forms of measurement bias in quantitative investigations. A defective scale would generate instrument bias and invalidate the experimental process in a quantitative experiment.

For example, you may ask those who do not have internet access to survey by email or on your website.

Data collection bias occurs in qualitative research when inappropriate survey questions are asked during an unstructured interview. Bad survey questions are those that lead the interviewee to make presumptions. Subjects are frequently hesitant to provide socially incorrect responses for fear of criticism.

For example, a topic can avoid coming across as homophobic or racist in an interview.

Some more types of bias in research include the ones listed here. Researchers must understand these biases and reduce them through rigorous study design, transparent reporting, and critical evidence review: 

  • Confirmation bias: Researchers often search for, evaluate, and prioritize material that supports their existing hypotheses or expectations, ignoring contradictory data. This can lead to a skewed perception of results and perhaps biased conclusions.
  • Cultural bias: Cultural bias arises when cultural norms, attitudes, or preconceptions influence the research process and the interpretation of results.
  • Funding bias: Funding bias takes place when powerful motives support research. It can bias research design, data collecting, analysis, and interpretation toward the funding source.
  • Observer bias: Observer bias arises when the researcher or observer affects participants’ replies or behavior. Collecting data might be biased by accidental clues, expectations, or subjective interpretations.

LEARN ABOUT: Theoretical Research

QuestionPro offers several features and functionalities that can contribute to reducing bias in the research process. Here’s how QuestionPro can help:

Randomization

QuestionPro allows researchers to randomize the order of survey questions or response alternatives. Randomization helps to remove order effects and limit bias from the order in which participants encounter the items.

Branching and skip logic

Branching and skip logic capabilities in QuestionPro allow researchers to design customized survey pathways based on participants’ responses. It enables tailored questioning, ensuring that only pertinent questions are asked of participants. Bias generated by such inquiries is reduced by avoiding irrelevant or needless questions.

Diverse question types

QuestionPro supports a wide range of questions kinds, including multiple-choice, Likert scale, matrix, and open-ended questions. Researchers can choose the most relevant question kinds to get unbiased data while avoiding leading or suggestive questions that may affect participants’ responses.

Anonymous responses

QuestionPro enables researchers to collect anonymous responses, protecting the confidentiality of participants. It can encourage participants to provide more unbiased and equitable feedback, especially when dealing with sensitive or contentious issues.

Data analysis and reporting

QuestionPro has powerful data analysis and reporting options, such as charts, graphs, and statistical analysis tools. These properties allow researchers to examine and interpret obtained data objectively, decreasing the role of bias in interpreting results.

Collaboration and peer review

QuestionPro supports peer review and researcher collaboration. It helps uncover and overcome biases in research planning, questionnaire formulation, and data analysis by involving several researchers and soliciting external opinions.

You must comprehend biases in research and how to deal with them. Knowing the different sorts of biases in research allows you to readily identify them. It is also necessary to have a clear idea to recognize it in any form.

QuestionPro provides many research tools and settings that can assist you in dealing with research bias. Try QuestionPro today to undertake your original bias-free quantitative or qualitative research.

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Frequently Asking Questions

Research bias affects the validity and dependability of your research’s findings, resulting in inaccurate interpretations of the data and incorrect conclusions.

Bias should be avoided in research to ensure that findings are accurate, valid, and objective.

 To avoid research bias, researchers should take proactive steps throughout the research process, such as developing a clear research question and objectives, designing a rigorous study, following standardized protocols, and so on.

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[Three types of bias: distortion of research results and how that can be prevented]

Affiliation.

  • 1 Universitair Medisch Centrum Utrecht, Julius Centrum voor Gezondheidswetenschappen en Eerstelijns Geneeskunde, Utrecht.
  • PMID: 25714762

A systematic distortion of the relationship between a treatment, risk factor or exposure and clinical outcomes is denoted by the term 'bias'. Three types of bias can be distinguished: information bias, selection bias, and confounding. These three types of bias and their potential solutions are discussed using various examples.

Publication types

  • Biomedical Research / standards*
  • Data Interpretation, Statistical
  • Risk Factors
  • Selection Bias*

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  • Research bias

Types of Bias in Research | Definition & Examples

Research bias results from any deviation from the truth, causing distorted results and wrong conclusions. Bias can occur at any phase of your research, including during data collection , data analysis , interpretation, or publication. Research bias can occur in both qualitative and quantitative research .

Understanding research bias is important for several reasons.

  • Bias exists in all research, across research designs , and is difficult to eliminate.
  • Bias can occur at any stage of the research process.
  • Bias impacts the validity and reliability of your findings, leading to misinterpretation of data.

It is almost impossible to conduct a study without some degree of research bias. It’s crucial for you to be aware of the potential types of bias, so you can minimise them.

For example, the success rate of the program will likely be affected if participants start to drop out. Participants who become disillusioned due to not losing weight may drop out, while those who succeed in losing weight are more likely to continue. This in turn may bias the findings towards more favorable results.  

Table of contents

Actor–observer bias.

  • Confirmation bias

Information bias

Interviewer bias.

  • Publication bias

Researcher bias

Response bias.

Selection bias

How to avoid bias in research

Other types of research bias, frequently asked questions about research bias.

Actor–observer bias occurs when you attribute the behaviour of others to internal factors, like skill or personality, but attribute your own behaviour to external or situational factors.

In other words, when you are the actor in a situation, you are more likely to link events to external factors, such as your surroundings or environment. However, when you are observing the behaviour of others, you are more likely to associate behaviour with their personality, nature, or temperament.

One interviewee recalls a morning when it was raining heavily. They were rushing to drop off their kids at school in order to get to work on time. As they were driving down the road, another car cut them off as they were trying to merge. They tell you how frustrated they felt and exclaim that the other driver must have been a very rude person.

At another point, the same interviewee recalls that they did something similar: accidentally cutting off another driver while trying to take the correct exit. However, this time, the interviewee claimed that they always drive very carefully, blaming their mistake on poor visibility due to the rain.

Confirmation bias is the tendency to seek out information in a way that supports our existing beliefs while also rejecting any information that contradicts those beliefs. Confirmation bias is often unintentional but still results in skewed results and poor decision-making.

Let’s say you grew up with a parent in the military. Chances are that you have a lot of complex emotions around overseas deployments. This can lead you to over-emphasise findings that ‘prove’ that your lived experience is the case for most families, neglecting other explanations and experiences.

Information bias , also called measurement bias, arises when key study variables are inaccurately measured or classified. Information bias occurs during the data collection step and is common in research studies that involve self-reporting and retrospective data collection. It can also result from poor interviewing techniques or differing levels of recall from participants.

The main types of information bias are:

  • Recall bias
  • Observer bias

Performance bias

Regression to the mean (rtm).

Over a period of four weeks, you ask students to keep a journal, noting how much time they spent on their smartphones along with any symptoms like muscle twitches, aches, or fatigue.

Recall bias is a type of information bias. It occurs when respondents are asked to recall events in the past and is common in studies that involve self-reporting.

As a rule of thumb, infrequent events (e.g., buying a house or a car) will be memorable for longer periods of time than routine events (e.g., daily use of public transportation). You can reduce recall bias by running a pilot survey and carefully testing recall periods. If possible, test both shorter and longer periods, checking for differences in recall.

  • A group of children who have been diagnosed, called the case group
  • A group of children who have not been diagnosed, called the control group

Since the parents are being asked to recall what their children generally ate over a period of several years, there is high potential for recall bias in the case group.

The best way to reduce recall bias is by ensuring your control group will have similar levels of recall bias to your case group. Parents of children who have childhood cancer, which is a serious health problem, are likely to be quite concerned about what may have contributed to the cancer.

Thus, if asked by researchers, these parents are likely to think very hard about what their child ate or did not eat in their first years of life. Parents of children with other serious health problems (aside from cancer) are also likely to be quite concerned about any diet-related question that researchers ask about.

Observer bias is the tendency of research participants to see what they expect or want to see, rather than what is actually occurring. Observer bias can affect the results in observationa l and experimental studies, where subjective judgement (such as assessing a medical image) or measurement (such as rounding blood pressure readings up or down) is part of the data collection process.

Observer bias leads to over- or underestimation of true values, which in turn compromise the validity of your findings. You can reduce observer bias by using double-  and single-blinded research methods.

Based on discussions you had with other researchers before starting your observations, you are inclined to think that medical staff tend to simply call each other when they need specific patient details or have questions about treatments.

At the end of the observation period, you compare notes with your colleague. Your conclusion was that medical staff tend to favor phone calls when seeking information, while your colleague noted down that medical staff mostly rely on face-to-face discussions. Seeing that your expectations may have influenced your observations, you and your colleague decide to conduct interviews with medical staff to clarify the observed events. Note: Observer bias and actor–observer bias are not the same thing.

Performance bias is unequal care between study groups. Performance bias occurs mainly in medical research experiments, if participants have knowledge of the planned intervention, therapy, or drug trial before it begins.

Studies about nutrition, exercise outcomes, or surgical interventions are very susceptible to this type of bias. It can be minimized by using blinding , which prevents participants and/or researchers from knowing who is in the control or treatment groups. If blinding is not possible, then using objective outcomes (such as hospital admission data) is the best approach.

When the subjects of an experimental study change or improve their behaviour because they are aware they are being studied, this is called the Hawthorne (or observer) effect . Similarly, the John Henry effect occurs when members of a control group are aware they are being compared to the experimental group. This causes them to alter their behaviour in an effort to compensate for their perceived disadvantage.

Regression to the mean (RTM) is a statistical phenomenon that refers to the fact that a variable that shows an extreme value on its first measurement will tend to be closer to the centre of its distribution on a second measurement.

Medical research is particularly sensitive to RTM. Here, interventions aimed at a group or a characteristic that is very different from the average (e.g., people with high blood pressure) will appear to be successful because of the regression to the mean. This can lead researchers to misinterpret results, describing a specific intervention as causal when the change in the extreme groups would have happened anyway.

In general, among people with depression, certain physical and mental characteristics have been observed to deviate from the population mean .

This could lead you to think that the intervention was effective when those treated showed improvement on measured post-treatment indicators, such as reduced severity of depressive episodes.

However, given that such characteristics deviate more from the population mean in people with depression than in people without depression, this improvement could be attributed to RTM.

Interviewer bias stems from the person conducting the research study. It can result from the way they ask questions or react to responses, but also from any aspect of their identity, such as their sex, ethnicity, social class, or perceived attractiveness.

Interviewer bias distorts responses, especially when the characteristics relate in some way to the research topic. Interviewer bias can also affect the interviewer’s ability to establish rapport with the interviewees, causing them to feel less comfortable giving their honest opinions about sensitive or personal topics.

Participant: ‘I like to solve puzzles, or sometimes do some gardening.’

You: ‘I love gardening, too!’

In this case, seeing your enthusiastic reaction could lead the participant to talk more about gardening.

Establishing trust between you and your interviewees is crucial in order to ensure that they feel comfortable opening up and revealing their true thoughts and feelings. At the same time, being overly empathetic can influence the responses of your interviewees, as seen above.

Publication bias occurs when the decision to publish research findings is based on their nature or the direction of their results. Studies reporting results that are perceived as positive, statistically significant , or favoring the study hypotheses are more likely to be published due to publication bias.

Publication bias is related to data dredging (also called p -hacking ), where statistical tests on a set of data are run until something statistically significant happens. As academic journals tend to prefer publishing statistically significant results, this can pressure researchers to only submit statistically significant results. P -hacking can also involve excluding participants or stopping data collection once a p value of 0.05 is reached. However, this leads to false positive results and an overrepresentation of positive results in published academic literature.

Researcher bias occurs when the researcher’s beliefs or expectations influence the research design or data collection process. Researcher bias can be deliberate (such as claiming that an intervention worked even if it didn’t) or unconscious (such as letting personal feelings, stereotypes, or assumptions influence research questions ).

The unconscious form of researcher bias is associated with the Pygmalion (or Rosenthal) effect, where the researcher’s high expectations (e.g., that patients assigned to a treatment group will succeed) lead to better performance and better outcomes.

Researcher bias is also sometimes called experimenter bias, but it applies to all types of investigative projects, rather than only to experimental designs .

  • Good question: What are your views on alcohol consumption among your peers?
  • Bad question: Do you think it’s okay for young people to drink so much?

Response bias is a general term used to describe a number of different situations where respondents tend to provide inaccurate or false answers to self-report questions, such as those asked on surveys or in structured interviews .

This happens because when people are asked a question (e.g., during an interview ), they integrate multiple sources of information to generate their responses. Because of that, any aspect of a research study may potentially bias a respondent. Examples include the phrasing of questions in surveys, how participants perceive the researcher, or the desire of the participant to please the researcher and to provide socially desirable responses.

Response bias also occurs in experimental medical research. When outcomes are based on patients’ reports, a placebo effect can occur. Here, patients report an improvement despite having received a placebo, not an active medical treatment.

While interviewing a student, you ask them:

‘Do you think it’s okay to cheat on an exam?’

Common types of response bias are:

Acquiescence bias

Demand characteristics.

  • Social desirability bias

Courtesy bias

  • Question-order bias

Extreme responding

Acquiescence bias is the tendency of respondents to agree with a statement when faced with binary response options like ‘agree/disagree’, ‘yes/no’, or ‘true/false’. Acquiescence is sometimes referred to as ‘yea-saying’.

This type of bias occurs either due to the participant’s personality (i.e., some people are more likely to agree with statements than disagree, regardless of their content) or because participants perceive the researcher as an expert and are more inclined to agree with the statements presented to them.

Q: Are you a social person?

People who are inclined to agree with statements presented to them are at risk of selecting the first option, even if it isn’t fully supported by their lived experiences.

In order to control for acquiescence, consider tweaking your phrasing to encourage respondents to make a choice truly based on their preferences. Here’s an example:

Q: What would you prefer?

  • A quiet night in
  • A night out with friends

Demand characteristics are cues that could reveal the research agenda to participants, risking a change in their behaviours or views. Ensuring that participants are not aware of the research goals is the best way to avoid this type of bias.

On each occasion, patients reported their pain as being less than prior to the operation. While at face value this seems to suggest that the operation does indeed lead to less pain, there is a demand characteristic at play. During the interviews, the researcher would unconsciously frown whenever patients reported more post-op pain. This increased the risk of patients figuring out that the researcher was hoping that the operation would have an advantageous effect.

Social desirability bias is the tendency of participants to give responses that they believe will be viewed favorably by the researcher or other participants. It often affects studies that focus on sensitive topics, such as alcohol consumption or sexual behaviour.

You are conducting face-to-face semi-structured interviews with a number of employees from different departments. When asked whether they would be interested in a smoking cessation program, there was widespread enthusiasm for the idea.

Note that while social desirability and demand characteristics may sound similar, there is a key difference between them. Social desirability is about conforming to social norms, while demand characteristics revolve around the purpose of the research.

Courtesy bias stems from a reluctance to give negative feedback, so as to be polite to the person asking the question. Small-group interviewing where participants relate in some way to each other (e.g., a student, a teacher, and a dean) is especially prone to this type of bias.

Question order bias

Question order bias occurs when the order in which interview questions are asked influences the way the respondent interprets and evaluates them. This occurs especially when previous questions provide context for subsequent questions.

When answering subsequent questions, respondents may orient their answers to previous questions (called a halo effect ), which can lead to systematic distortion of the responses.

Extreme responding is the tendency of a respondent to answer in the extreme, choosing the lowest or highest response available, even if that is not their true opinion. Extreme responding is common in surveys using Likert scales , and it distorts people’s true attitudes and opinions.

Disposition towards the survey can be a source of extreme responding, as well as cultural components. For example, people coming from collectivist cultures tend to exhibit extreme responses in terms of agreement, while respondents indifferent to the questions asked may exhibit extreme responses in terms of disagreement.

Selection bias is a general term describing situations where bias is introduced into the research from factors affecting the study population.

Common types of selection bias are:

Sampling or ascertainment bias

  • Attrition bias

Volunteer or self-selection bias

  • Survivorship bias
  • Nonresponse bias
  • Undercoverage bias

Sampling bias occurs when your sample (the individuals, groups, or data you obtain for your research) is selected in a way that is not representative of the population you are analyzing. Sampling bias threatens the external validity of your findings and influences the generalizability of your results.

The easiest way to prevent sampling bias is to use a probability sampling method . This way, each member of the population you are studying has an equal chance of being included in your sample.

Sampling bias is often referred to as ascertainment bias in the medical field.

Attrition bias occurs when participants who drop out of a study systematically differ from those who remain in the study. Attrition bias is especially problematic in randomized controlled trials for medical research because participants who do not like the experience or have unwanted side effects can drop out and affect your results.

You can minimize attrition bias by offering incentives for participants to complete the study (e.g., a gift card if they successfully attend every session). It’s also a good practice to recruit more participants than you need, or minimize the number of follow-up sessions or questions.

You provide a treatment group with weekly one-hour sessions over a two-month period, while a control group attends sessions on an unrelated topic. You complete five waves of data collection to compare outcomes: a pretest survey , three surveys during the program, and a posttest survey.

Volunteer bias (also called self-selection bias ) occurs when individuals who volunteer for a study have particular characteristics that matter for the purposes of the study.

Volunteer bias leads to biased data, as the respondents who choose to participate will not represent your entire target population. You can avoid this type of bias by using random assignment – i.e., placing participants in a control group or a treatment group after they have volunteered to participate in the study.

Closely related to volunteer bias is nonresponse bias , which occurs when a research subject declines to participate in a particular study or drops out before the study’s completion.

Considering that the hospital is located in an affluent part of the city, volunteers are more likely to have a higher socioeconomic standing, higher education, and better nutrition than the general population.

Survivorship bias occurs when you do not evaluate your data set in its entirety: for example, by only analyzing the patients who survived a clinical trial.

This strongly increases the likelihood that you draw (incorrect) conclusions based upon those who have passed some sort of selection process – focusing on ‘survivors’ and forgetting those who went through a similar process and did not survive.

Note that ‘survival’ does not always mean that participants died! Rather, it signifies that participants did not successfully complete the intervention.

However, most college dropouts do not become billionaires. In fact, there are many more aspiring entrepreneurs who dropped out of college to start companies and failed than succeeded.

Nonresponse bias occurs when those who do not respond to a survey or research project are different from those who do in ways that are critical to the goals of the research. This is very common in survey research, when participants are unable or unwilling to participate due to factors like lack of the necessary skills, lack of time, or guilt or shame related to the topic.

You can mitigate nonresponse bias by offering the survey in different formats (e.g., an online survey, but also a paper version sent via post), ensuring confidentiality , and sending them reminders to complete the survey.

You notice that your surveys were conducted during business hours, when the working-age residents were less likely to be home.

Undercoverage bias occurs when you only sample from a subset of the population you are interested in. Online surveys can be particularly susceptible to undercoverage bias. Despite being more cost-effective than other methods, they can introduce undercoverage bias as a result of excluding people who do not use the internet.

While very difficult to eliminate entirely, research bias can be mitigated through proper study design and implementation. Here are some tips to keep in mind as you get started.

  • Clearly explain in your methodology section how your research design will help you meet the research objectives and why this is the most appropriate research design.
  • In quantitative studies , make sure that you use probability sampling to select the participants. If you’re running an experiment, make sure you use random assignment to assign your control and treatment groups.
  • Account for participants who withdraw or are lost to follow-up during the study. If they are withdrawing for a particular reason, it could bias your results. This applies especially to longer-term or longitudinal studies .
  • Use triangulation to enhance the validity and credibility of your findings.
  • Phrase your survey or interview questions in a neutral, non-judgemental tone. Be very careful that your questions do not steer your participants in any particular direction.
  • Consider using a reflexive journal. Here, you can log the details of each interview , paying special attention to any influence you may have had on participants. You can include these in your final analysis.

Cognitive bias

  • Baader–Meinhof phenomenon
  • Availability heuristic
  • Halo effect
  • Framing effect
  • Sampling bias
  • Ascertainment bias
  • Self-selection bias
  • Hawthorne effect
  • Omitted variable bias
  • Pygmalion effect
  • Placebo effect

Bias in research affects the validity and reliability of your findings, leading to false conclusions and a misinterpretation of the truth. This can have serious implications in areas like medical research where, for example, a new form of treatment may be evaluated.

Observer bias occurs when the researcher’s assumptions, views, or preconceptions influence what they see and record in a study, while actor–observer bias refers to situations where respondents attribute internal factors (e.g., bad character) to justify other’s behaviour and external factors (difficult circumstances) to justify the same behaviour in themselves.

Response bias is a general term used to describe a number of different conditions or factors that cue respondents to provide inaccurate or false answers during surveys or interviews . These factors range from the interviewer’s perceived social position or appearance to the the phrasing of questions in surveys.

Nonresponse bias occurs when the people who complete a survey are different from those who did not, in ways that are relevant to the research topic. Nonresponse can happen either because people are not willing or not able to participate.

Is this article helpful?

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  • Attrition Bias | Examples, Explanation, Prevention
  • Demand Characteristics | Definition, Examples & Control
  • Hostile Attribution Bias | Definition & Examples
  • Observer Bias | Definition, Examples, Prevention
  • Regression to the Mean | Definition & Examples
  • Representativeness Heuristic | Example & Definition
  • Sampling Bias and How to Avoid It | Types & Examples
  • Self-Fulfilling Prophecy | Definition & Examples
  • The Availability Heuristic | Example & Definition
  • The Baader–Meinhof Phenomenon Explained
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  • What Is Ascertainment Bias? | Definition & Examples
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  • What Is Bias for Action? | Definition & Examples
  • What Is Cognitive Bias? | Meaning, Types & Examples
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  • What Is Implicit Bias? | Definition & Examples
  • What Is Information Bias? | Definition & Examples
  • What Is Ingroup Bias? | Definition & Examples
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  • What Is Nonresponse Bias?| Definition & Example
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  • What Is Omitted Variable Bias? | Definition & Example
  • What Is Optimism Bias? | Definition & Examples
  • What Is Outgroup Bias? | Definition & Examples
  • What Is Overconfidence Bias? | Definition & Examples
  • What Is Perception Bias? | Definition & Examples
  • What Is Primacy Bias? | Definition & Example
  • What Is Publication Bias? | Definition & Examples
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  • What Is Response Bias? | Definition & Examples
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  • What Is Self-Selection Bias? | Definition & Example
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  • What Is Social Desirability Bias? | Definition & Examples
  • What Is Status Quo Bias? | Definition & Examples
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  • What Is the Halo Effect? | Definition & Examples
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  • CAREER FEATURE
  • 08 May 2024

Illuminating ‘the ugly side of science’: fresh incentives for reporting negative results

  • Rachel Brazil 0

Rachel Brazil is a freelance journalist in London, UK.

You can also search for this author in PubMed   Google Scholar

Sarahanne Field giving a talk

The editor-in-chief of the Journal of Trial & Error , Sarahanne Field wants to publish the messy, null and negative results sitting in researchers’ file drawers. Credit: Sander Martens

Editor-in-chief Sarahanne Field describes herself and her team at the Journal of Trial & Error as wanting to highlight the “ugly side of science — the parts of the process that have gone wrong”.

She clarifies that the editorial board of the journal, which launched in 2020 , isn’t interested in papers in which “you did a shitty study and you found nothing. We’re interested in stuff that was done methodologically soundly, but still yielded a result that was unexpected.” These types of result — which do not prove a hypothesis or could yield unexplained outcomes — often simply go unpublished, explains Field, who is also an open-science researcher at the University of Groningen in the Netherlands. Along with Stefan Gaillard, one of the journal’s founders, she hopes to change that.

Calls for researchers to publish failed studies are not new. The ‘file-drawer problem’ — the stacks of unpublished, negative results that most researchers accumulate — was first described in 1979 by psychologist Robert Rosenthal . He argued that this leads to publication bias in the scientific record: the gap of missing unsuccessful results leads to overemphasis on the positive results that do get published.

research results bias

Careers Collection: Publishing

Over the past 30 years, the proportion of negative results being published has decreased further. A 2012 study showed that, from 1990 to 2007, there was a 22% increase in positive conclusions in papers; by 2007, 85% of papers published had positive results 1 . “People fail to report [negative] results, because they know they won’t get published — and when people do attempt to publish them, they get rejected,” says Field. A 2022 survey of researchers in France in chemistry, physics, engineering and environmental sciences showed that, although 81% had produced relevant negative results and 75% were willing to publish them, only 12.5% had the opportunity to do so 2 .

One factor that is leading some researchers to revisit the problem is the growing use of predictive modelling using machine-learning tools in many fields. These tools are trained on large data sets that are often derived from published work, and scientists have found that the absence of negative data in the literature is hampering the process. Without a concerted effort to publish more negative results that artificial intelligence (AI) can be trained on, the promise of the technology could be stifled.

“Machine learning is changing how we think about data,” says chemist Keisuke Takahashi at Hokkaido University in Japan, who has brought the issue to the attention of the catalysis-research community . Scientists in the field have typically relied on a mixture of trial and error and serendipity in their experiments, but there is hope that AI could provide a new route for catalyst discovery. Takahashi and his colleagues mined data from 1,866 previous studies and patents to train a machine-learning model to predict the best catalyst for the reaction between methane and oxygen to form ethane and ethylene, both of which are important chemicals used in industry 3 . But, he says, “over the years, people have only collected the good data — if they fail, they don’t report it”. This led to a skewed model that, in some cases, enhanced the predicted performance of a material, rather than realistically assessing its properties.

Portrait of Felix Strieth-Kalthoff in the lab

Synthetic organic chemist Felix Strieth-Kalthoff found that published data were too heavily biased toward positive results to effectively train an AI model to optimize chemical reaction yields. Credit: Cindy Huang

Alongside the flawed training of AI models, the huge gap of negative results in the scientific record continues to be a problem across all disciplines. In areas such as psychology and medicine, publication bias is one factor exacerbating the ongoing reproducibility crisis — in which many published studies are impossible to replicate. Without sharing negative studies and data, researchers could be doomed to repeat work that led nowhere. Many scientists are calling for changes in academic culture and practice — be it the creation of repositories that include positive and negative data, new publication formats or conferences aimed at discussing failure. The solutions are varied, but the message is the same: “To convey an accurate picture of the scientific process, then at least one of the components should be communicating all the results, [including] some negative results,” says Gaillard, “and even where you don’t end up with results, where it just goes wrong.”

Science’s messy side

Synthetic organic chemist Felix Strieth-Kalthoff, who is now setting up his own laboratory at the University of Wuppertal, Germany, has encountered positive-result bias when using data-driven approaches to optimize the yields of certain medicinal-chemistry reactions. His PhD work with chemist Frank Glorius at the University of Münster, Germany, involved creating models that could predict which reactants and conditions would maximize yields. Initially, he relied on data sets that he had generated from high-throughput experiments in the lab, which included results from both high- and low-yield reactions, to train his AI model. “Our next logical step was to do that based on the literature,” says Strieth-Kalthoff. This would allow him to curate a much larger data set to be used for training.

But when he incorporated real data from the reactions database Reaxys into the training process, he says, “[it] turned out they don’t really work at all”. Strieth-Kalthoff concluded the errors were due the lack of low-yield reactions 4 ; “All of the data that we see in the literature have average yields of 60–80%.” Without learning from the messy ‘failed’ experiments with low yields that were present in the initial real-life data, the AI could not model realistic reaction outcomes.

Although AI has the potential to spot relationships in complex data that a researcher might not see, encountering negative results can give experimentalists a gut feeling, says molecular modeller Berend Smit at the Swiss Federal Institute of Technology Lausanne. The usual failures that every chemist experiences at the bench give them a ‘chemical intuition’ that AI models trained only on successful data lack.

Smit and his team attempted to embed something similar to this human intuition into a model tasked with designing a metal-organic framework (MOF) with the largest known surface area for this type of material. A large surface area allows these porous materials to be used as reaction supports or molecular storage reservoirs. “If the binding [between components] is too strong, it becomes amorphous; if the binding is too weak, it becomes unstable, so you need to find the sweet spot,” Smit says. He showed that training the machine-learning model on both successful and unsuccessful reaction conditions created better predictions and ultimately led to one that successfully optimized the MOF 5 . “When we saw the results, we thought, ‘Wow, this is the chemical intuition we’re talking about!’” he says.

According to Strieth-Kalthoff, AI models are currently limited because “the data that are out there just do not reflect all of our knowledge”. Some researchers have sought statistical solutions to fill the negative-data gap. Techniques include oversampling, which means supplementing data with several copies of existing negative data or creating artificial data points, for example by including reactions with a yield of zero. But, he says, these types of approach can introduce their own biases.

Portrait of Ella Peltonen

Computer scientist Ella Peltonen helped to organize the first International Workshop on Negative Results in Pervasive Computing in 2022 to give researchers an opportunity to discuss failed experiments. Credit: University of Oulu

Capturing more negative data is now a priority for Takahashi. “We definitely need some sort of infrastructure to share the data freely.” His group has created a website for sharing large amounts of experimental data for catalysis reactions . Other organizations are trying to collect and publish negative data — but Takahashi says that, so far, they lack coordination, so data formats aren’t standardized. In his field, Strieth-Kalthoff says, there are initiatives such as the Open Reaction Database , launched in 2021 to share organic-reaction data and enable training of machine-learning applications. But, he says, “right now, nobody’s using it, [because] there’s no incentive”.

Smit has argued for a modular open-science platform that would directly link to electronic lab notebooks to help to make different data types extractable and reusable . Through this process, publication of negative data in peer-reviewed journals could be skipped, but the information would still be available for researchers to use in AI training. Strieth-Kalthoff agrees with this strategy in theory, but thinks it’s a long way off in practice, because it would require analytical instruments to be coupled to a third-party source to automatically collect data — which instrument manufacturers might not agree to, he says.

Publishing the non-positive

In other disciplines, the emphasis is still on peer-reviewed journals that will publish negative results. Gaillard, a science-studies PhD student at Radboud University in Nijmegen, the Netherlands, co-founded the Journal of Trial & Error after attending talks on how science can be made more open. Gaillard says that, although everyone whom they approached liked the idea of the journal, nobody wanted to submit articles at first. He and the founding editorial team embarked on a campaign involving cold calls and publicity at open-science conferences. “Slowly, we started getting our first submissions, and now we just get people sending things in [unsolicited],” he says. Most years the journal publishes one issue of about 8–14 articles, and it is starting to publish more special issues. It focuses mainly on the life sciences and data-based social sciences.

In 2008, David Alcantara, then a chemistry PhD student at the University of Seville in Spain who was frustrated by the lack of platforms for sharing negative results, set up The All Results journals, which were aimed at disseminating results regardless of the outcome . Of the four disciplines included at launch, only the biology journal is still being published. “Attracting submissions has always posed a challenge,” says Alcantara, now president at the consultancy and training organization the Society for the Improvement of Science in Seville.

But Alcantara thinks there has been a shift in attitudes: “More established journals [are] becoming increasingly open to considering negative results for publication.” Gaillard agrees: “I’ve seen more and more journals, like PLoS ONE , for example, that explicitly mentioned that they also publish negative results.” ( Nature welcomes submissions of replication studies and those that include null results, as described in this 2020 editorial .)

Journals might be changing their publication preferences, but there are still significant disincentives that stop researchers from publishing their file-drawer studies. “The current academic system often prioritizes high-impact publications and ground-breaking discoveries for career advancement, grants and tenure,” says Alcantara, noting that negative results are perceived as contributing little to nothing to these endeavours. Plus, there is still a stigma associated with any kind of failure . “People are afraid that this will look negative on their CV,” says Gaillard. Smit describes reporting failed experiments as a no-win situation: “It’s more work for [researchers], and they don’t get anything in return in the short term.” And, jokes Smit, what’s worse is that they could be providing data for an AI tool to take over their role.

Ultimately, most researchers conclude that publishing their failed studies and negative data is just not worth the time and effort — and there’s evidence that they judge others’ negative research more harshly than positive outcomes. In a study published in August, 500 researchers from top economics departments around the world were randomized to two groups and asked to judge a hypothetical research paper. Half of the participants were told that the study had a null conclusion, and the other half were told the results were sizeably significant. The null results were perceived to be 25% less likely to be published, of lower quality and less important than were the statistically significant findings 6 .

Some researchers have had positive experiences sharing their unsuccessful findings. For example, in 2021, psychologist Wendy Ross at the London Metropolitan University published her negative results from testing a hypothesis about human problem-solving in the Journal of Trial & Error 7 , and says the paper was “the best one I have published to date”. She adds, “Understanding the reasons for null results can really test and expand our theoretical understanding.”

Fields forging solutions

The field of psychology has introduced one innovation that could change publication biases — registered reports (RRs). These peer-reviewed reports , first published in 2014, came about largely as a response to psychology’s replication crisis, which began in around 2011. RRs set out the methodology of a study before the results are known, to try to prevent selective reporting of positive results. Daniël Lakens, who studies science-reward structures at Eindhoven University of Technology in the Netherlands, says there is evidence that RRs increase the proportion of negative results in the psychology literature.

In a 2021 study, Lakens analysed the proportion of published RRs whose results eventually support the primary hypothesis. In a random sample of hypothesis-testing studies from the standard psychology literature, 96% of the results were positive. In RRs, this fell to only 44% 8 . Lakens says the study shows “that if you offer this as an option, many more null results enter the scientific literature, and that is a desirable thing”. At least 300 journals, including Nature , are now accepting RRs, and the format is spreading to journals in biology, medicine and some social-science fields.

Yet another approach has emerged from the field of pervasive computing, the study of how computer systems are integrated into physical surroundings and everyday life. About four years ago, members of the community started discussing reproducibility, says computer scientist Ella Peltonen at the University of Oulu in Finland. Peltonen says that researchers realized that, to avoid the repetition of mistakes, there was a need to discuss the practical problems with studies and failed results that don’t get published. So in 2022, Peltonen and her colleagues held the first virtual International Workshop on Negative Results in Pervasive Computing (PerFail) , in conjunction with the field’s annual conference, the International Conference on Pervasive Computing and Communications.

Peltonen explains that PerFail speakers first present their negative results and then have the same amount of time for discussion afterwards, during which participants tease out how failed studies can inform future work. “It also encourages the community to showcase that things require effort and trial and error, and there is value in that,” she adds. Now an annual event, the organizers invite students to attend so they can see that failure is a part of research and that “you are not a bad researcher because you fail”, says Peltonen.

In the long run, Alcantara thinks a continued effort to persuade scientists to share all their results needs to be coupled with policies at funding agencies and journals that reward full transparency. “Criteria for grants, promotions and tenure should recognize the value of comprehensive research dissemination, including failures and negative outcomes,” he says. Lakens thinks funders could be key to boosting the RR format, as well. Funders, he adds, should say, “We want the research that we’re funding to appear in the scientific literature, regardless of the significance of the finding.”

There are some positive signs of change about sharing negative data: “Early-career researchers and the next generation of scientists are particularly receptive to the idea,” says Alcantara. Gaillard is also optimistic, given the increased interest in his journal, including submissions for an upcoming special issue on mistakes in the medical domain. “It is slow, of course, but science is a bit slow.”

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May 4, 2024

Implicit Bias Hurts Everyone. Here’s How to Overcome It

The environment shapes stereotypes and biases, but it is possible to recognize and change them

By Corey S. Powell & OpenMind Magazine

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We all have a natural tendency to view the world in black and white—to the extent that it's hard not to hear "black" and immediately think "white." Fortunately, there are ways to activate the more subtle shadings in our minds. Kristin Pauker is a professor of psychology at the University of Hawaiʻi at Mānoa who studies stereotyping and prejudice, with a focus on how our environment shapes our biases. In this podcast and Q&A, she tells OpenMind co-editor Corey S. Powell how researchers measure and study bias, and how we can use their findings to make a more equitable world. (This conversation has been edited for length and clarity.)

When I hear “bias,” the first thing I think of is a conscious prejudice. But you study something a lot more subtle, which researchers call “implicit bias.” What is it, and how does it affect us?

Implicit bias is a form of bias that influences our decision-making, our interactions and our behaviors. It can be based on any social group membership, like race, gender, age, sexual orientation or even the color of your shirt. Often we’re not aware of the ways in which these biases are influencing us. Sometimes implicit bias gets called unconscious bias, which is a little bit of a misnomer. We can be aware of these biases, so it's not necessarily unconscious. But we often are not aware of the way in which they're influencing our behaviors and thoughts.

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You make it sound like almost anything can set us off. Why is bias so deeply ingrained in our heads?

Our brain likes to categorize things because it makes our world easier to process. We make categories as soon as we start learning about something. So we categorize fruits, we categorize vegetables, we categorize chairs, we categorize tables for their function—and we also categorize people. We know from research that categorization happens early in life, as early as 5 or 6, in some cases even 3 or 4. Categorization creates shortcuts that help us process information faster, but that also can lead us to make assumptions that may or may not hold in particular situations. What categories we use are directed by the environment that we're in. Our environment already has told us certain categories are really important, such as gender, age, race and ethnicity. We quickly form an association when we’re assigned to a particular group.

Listen to the Podcast

Kristin Pauker: We have to think about ways in which we can change the features of our environment—so that our weeds aren’t so prolific.

In your research, you use a diagnostic tool called an “ implicit association test .” How does it work, and what does it tell you?

Typically someone would show you examples of individuals who belong to categories, and then ask you to categorize those individuals. For example, you would see faces and you would categorize them as black and white. You’re asked to make a fast categorization, as fast as you can. Then you are presented with words that could be categorized as good or bad, like “hero” and “evil,” and again asked to categorize the words quickly. The complicated part happens when, say, good and white are paired together or bad and black are paired together. You're asked to categorize the faces and the words as you were before. Then it's flipped, so that bad and white are paired together, and good and black are paired together. You’re asked to make the categorizations once again with the new pairings.

The point of the test is, how quickly do you associate certain concepts together? Oftentimes if certain concepts are more closely paired in your mind, then it will be easier for you to make that association. Your response will be faster. When the pairing is less familiar to you or less closely associated, it takes you longer to respond. Additional processing needs to occur.

When you run this implicit association test on your test subjects or your students, are they often surprised by the results?

We’ve done it as a demonstration in the classroom, and I've had students come up and complain saying, “There’s something wrong with this test. I don't believe it.” They’ll try to poke all kinds of holes in the test because it gave them a score that wasn’t what they felt it should be according to what they think about themselves. This is the case, I think, for almost anyone. I've taken an implicit association test and found that I have a stronger association with men in science than women in science . And I'm a woman scientist! We can have and hold these biases because they’re prevalent in society, even if they’re biases that may not be beneficial to the group we belong to.

Studies show that even after you make people aware of their implicit biases, they can’t necessarily get rid of them. So are we stuck with our biases?

Those biases are hard to change and control, but that doesn't mean that they are un controllable and un changeable. It’s just that oftentimes there are many features in our environment that reinforce those biases. I was thinking about an analogy. Right now I’m struggling with weeds growing in my yard, invasive vines. It’s hard because there are so many things supporting the growth of these vines. I live in a place that has lots of sun and rain. Similarly, there’s so much in our environment that is supporting our biases. It’s hard to just cut them off and be like, OK, they're gone. We have to think about ways in which we can change the features of our environment—so that our weeds aren’t so prolific.

Common programs aimed at reducing bias, such as corporate diversity training workshops, often seem to stop at the stage of making people aware that bias exists. Is that why they haven’t worked very well ?

If people are told that they’re biased, the reaction that many of them have is, “Oh, that means I'm a racist? I'm not a racist!” Very defensive, because we associate this idea of being biased with a moral judgment that I'm a bad person. Because of that, awareness-raising can have the opposite of the intended effect. Being told that they're biased can make people worried and defensive, and they push back against that idea. They're not willing to accept it.

A lot of the diversity training models are based on the idea that you can just tell people about their biases and then get them to accept them and work on them. But, A, some people don't want to accept their biases. B, some people don't want to work on them. And C, the messaging around how we talk about these biases creates a misunderstanding that they can’t be changed. We talk about biases that are unconscious, biases that we all hold, that are formed early in life—it creates the idea, “Well, there’s nothing I can do, so why should I even try?”

How can we do better in talking about bias, so that people are more likely to embrace change instead of becoming defensive or defeated?

Some of it is about messaging. Biases are hard to change, but we should be discussing the ways in which these biases can change, even though it might take some time and work. You have to emphasize the idea that these things can change, or else why would we try? There is research showing that if you just give people their bias score, normally that doesn't result in them becoming more aware of their bias. But if you combine that score with a message that this is something controllable, people are less defensive and more willing to accept their biases.

What about concrete actions we can take to reduce the negative impact of implicit bias?

One thing is thinking about when we do interventions. A lot of times we’re trying to make changes in the workplace. We should be thinking more about how we're raising our children. The types of environments we're exposing them to, and the features that are in our schools , are good places to think about creating change. Prejudice is something that’s malleable.

Another thing is not always focusing on the person. So much of what we do in these interventions is try to change individual people's biases. But we can also think about our environment. What are the ways in which our environments are communicating these biases, and how can we make changes there? A clever idea people have been thinking about is trying to change consequences of biases. There's a researcher, Jason A. Okonofua , who talks about this and calls it “sidelining bias.” You're not targeting the person and trying to get rid of their biases. You're targeting the situations that support those biases. If you can change that situation and kind of cut it off, then the consequences of bias might not be as bad. It could lead to a judgment that is not so influenced by those biases.

There’s research showing that people make fairer hiring decisions when they work off tightly structured interviews and qualification checklists, which leave less room for subjective reactions. Is that the kind of “sidelining” strategy you’re talking about?

Yes, that’s been shown to be an effective way to sideline bias. If you set those criteria ahead of time, it's harder for you to shift a preference based on the person that you would like to hire. Another good example is finding ways to slow down the processes we're working on. Biases are more likely to influence our decision-making when we have to make really quick decisions or when we are stressed—which is the case for a lot of important decisions that we make.

Jennifer Eberhardt does research on these kinds of implicit biases. She worked with NextDoor (a neighborhood monitoring app) when they noticed a lot of racial profiling in the things people were reporting in their neighborhood. She worked with them to change the way that people report a suspicious person. Basically they added some extra steps to the checklist when you report something. Rather than just reporting that someone looks suspicious, a user had to indicate what about the behavior itself was suspicious. And then there was an explicit warning that they couldn't just say the reason for the suspicious behavior was someone's race. Including extra check steps slowed down the process and reduced the profiling.

It does feel like we’re making progress in addressing bias but, damn, it’s been a slow process. Where can we go from here?

A big part that’s missing in the research on implicit bias is creating tools that are useful for people. We still don’t know a lot about bias, but we know a lot more than we're willing to put into practice. For instance, creating resources for parents to be able to have conversations about bias , and to be aware that the everyday things we do are really important. This is something that many people want to tackle, but they don’t know how to do it. Just asking questions about what is usual and what is unusual has really interesting effects. We’ve done that with our son. He’d say something and I would ask, “Why is that something that only boys can do? You say girls can't do that, is that really the case? Can you think of examples where the opposite is true?”

This Q&A is part of a series of OpenMind essays, podcasts and videos supported by a generous grant from the Pulitzer Center 's Truth Decay initiative.

This story originally appeared on OpenMind , a digital magazine tackling science controversies and deceptions.

More From Forbes

4 simple interventions to reduce biases against women at work.

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Women continue to report gender discrimination, especially in tech domains and in access to leadership roles. Among tech workers, 26% report they’ve experienced gender discrimination, according to one study .

Implicit bias training, while popular, often falls short; it typically fails to produce lasting behavioral change and can even reinforce stereotypes rather than eliminate them. An alternative approach involves redesigning organizational processes to manage and minimize the impact of biases.

Here are 4 simple, scientifically validated strategies to reduce gender bias in recruiting, selection and promotions.

Extend Your Shortlist Of Candidates

Despite formal job postings and promotion processes, hiring teams frequently resort to informal referrals. This results in male-heavy candidate shortlists in sectors like business and tech, where stereotypes favor men in tech and leadership positions.

Simply asking the hiring team to identify additional candidates for the shortlist should generate more women candidates, according to a series of ten studies published in Nature Human Behaviour. If you typically rely on a three-person shortlist, double it to include six people. Or ask the hiring team for a longer shortlist right at the start of the process.

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Extending the shortlist forces the hiring team to consider a broader range of candidates, which requires deeper thought and effort. This additional effort can disrupt automatic thought patterns, such as implicit biases, making it more likely that individuals outside the usual demographic — in this case, women in tech and leadership roles — are considered. This is how the study’s authors explain these results.

Show The Number Of Applicants For Job Postings

Information about advertised jobs is often lacking, potentially deterring women from applying to positions in male-dominated fields.

“Showing the number of current applicants on the corresponding job posting increases a job seeker’s likelihood of applying by 1.9%–3.6%,” according to an analysis of the behavior of 2.3 million real job applicants and 100,000 real job postings on LinkedIn. That percentage point difference corresponds to over 1,500 additional applications, according to Laura Gee, the study’s author.

Rather than signal that there is more competition for the job, knowing how many people have already applied provides an additional point of information about the job that could increase women’s comfort with it, encouraging them to apply to jobs, especially those dominated by men, as Gee explains it in her study.

Ask For Job Tenure In Years On Résumés

Résumés with career gaps, often from family duties, face extra scrutiny. This tends to disadvantage women, even if they're well-qualified.

Asking applicants to format their experience using years spent in each of their jobs (rather than start and end dates) increases the chance that hiring teams reach out to them. It minimizes the visibility of employment gaps and focuses attention on applicants’ cumulative experience. Listing the number of years on the job increases by 15% the likelihood that women applicants with career gaps receive a call-back. This is the finding from an intervention study published in Human Nature Behaviour, involving over 9,000 résumés sent to UK employers

Résumé formatting instructions can be communicated in job postings or application forms. Applicants could simply be told to convert the start and end dates for each position they have held (e.g., "June 2008 to May 2021") in the total years they held in that position (e.g., "13 years.")

Requesting applicants to report job tenure in years on their résumés helps to minimize the visibility of employment gaps. This approach focuses attention on the cumulative experience rather than specific periods of unemployment or career breaks. Consequently, it reduces the likelihood of biases against women who have taken breaks from their careers.

Check The Length Of Your Rating Scale

Even though gender biases aren't as strong as they used to be, women still face tougher standards, get less credit for the same work as men and are judged more harshly for mistakes. Tweaking the appraisal system could speed up change.

When evaluating candidates for jobs and promotions, switching from a broad scale (e.g., from 1 to 10) to a narrower, 6-point scale can significantly decrease bias. This method has been validated in a male-dominated university setting, where a narrower scale was found to effectively minimize gender bias in performance evaluations.

Scales with fewer points do not allow for the recording of subtle biases because they do not offer opportunities to express as much nuance, the authors of the study explain. When a scale has more categories, the highest rating on the scale is more likely to be associated with perfection and brilliance, attributes that are disproportionately less attainable for women, due to the implicit biases in performance evaluations. On smaller scales, the highest point level (e.g., 6) does not connote similar levels of perfection, the authors find.

By implementing these four research-based strategies, organizations can actively reduce gender bias in male-dominated fields. These interventions, essential for closing the gender gap, can foster inclusivity and equity.

Did you enjoy this story? Don’t miss my next one: Use the blue follow button at the top of the article near my byline to follow more of my work.

Corinne Post

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IMAGES

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  2. 15 Statistical Bias Examples (2024)

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  3. Research bias: What it is, Types & Examples

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  4. Strategies For Minimizing Bias In A Study: A Comprehensive Guide

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  5. Types of Bias in Research

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COMMENTS

  1. Types of Bias in Research

    Confirmation bias is the tendency to seek out information in a way that supports our existing beliefs while also rejecting any information that contradicts those beliefs. Confirmation bias is often unintentional but still results in skewed results and poor decision-making. Example: Confirmation bias in research.

  2. Identifying and Avoiding Bias in Research

    Abstract. This narrative review provides an overview on the topic of bias as part of Plastic and Reconstructive Surgery 's series of articles on evidence-based medicine. Bias can occur in the planning, data collection, analysis, and publication phases of research. Understanding research bias allows readers to critically and independently review ...

  3. Moving towards less biased research

    Introduction. Bias, perhaps best described as 'any process at any stage of inference which tends to produce results or conclusions that differ systematically from the truth,' can pollute the entire spectrum of research, including its design, analysis, interpretation and reporting. 1 It can taint entire bodies of research as much as it can individual studies. 2 3 Given this extensive ...

  4. Research Bias 101: Definition + Examples

    Research bias refers to any instance where the researcher, or the research design, negatively influences the quality of a study's results, whether intentionally or not. The three common types of research bias we looked at are: Selection bias - where a skewed sample leads to skewed results. Analysis bias - where the analysis method and/or ...

  5. Study Bias

    There are numerous sources of bias within the research process, ranging from the design and planning stage, data collection and analysis, interpretation of results, and the publication process. Bias in one or multiple points of this process can skew results and even lead to incorrect conclusions.

  6. Revisiting Bias in Qualitative Research: Reflections on Its

    Bias—commonly understood to be any influence that provides a distortion in the results of a study (Polit & Beck, 2014)—is a term drawn from the quantitative research paradigm.Most (though perhaps not all) of us would recognize the concept as being incompatible with the philosophical underpinnings of qualitative inquiry (Thorne, Stephens, & Truant, 2016).

  7. Best Available Evidence or Truth for the Moment: Bias in Research

    Abstract. The subject of this column is the nature of bias in both quantitative and qualitative research. To that end, bias will be defined and then both the processes by which it enters into research will be entertained along with discussions on how to ameliorate this problem. Clinicians, who are in practice, frequently are called upon to make ...

  8. Bias in Research

    Research bias can affect the validity and credibility of research findings, leading to erroneous conclusions. It can emerge from the researcher's subconscious preferences or the methodological design of the study itself. For instance, if a researcher unconsciously favors a particular outcome of the study, this preference could affect how they interpret the results, leading to a type of bias ...

  9. How bias affects scientific research

    Researcher bias occurs when the researcher conducting the study is in favor of a certain result. Researchers can influence outcomes through their study design choices, including who they choose to ...

  10. Bias in research

    What is bias in relation to research and why is understanding bias important? Bias is defined by the Oxford Dictionary as: "an inclination or prejudice for or against one person or group, especially in a way considered to be unfair"; "a concentration on an interest in one particular area or subject"; "a systematic distortion of statistical results due to a factor not allowed for in ...

  11. Research Bias: Definition, Types + Examples

    In qualitative research, data collection bias happens when you ask bad survey questions during a semi-structured or unstructured interview. Bad survey questions are questions that nudge the interviewee towards implied assumptions. Leading and loaded questions are common examples of bad survey questions. Procedural Bias.

  12. Sampling Bias and How to Avoid It

    Revised on March 17, 2023. Sampling bias occurs when some members of a population are systematically more likely to be selected in a sample than others. It is also called ascertainment bias in medical fields. Sampling bias limits the generalizability of findings because it is a threat to external validity, specifically population validity.

  13. What Is Publication Bias?

    Publication bias refers to the selective publication of research studies based on their results. Here, studies with positive findings are more likely to be published than studies with negative findings. Positive findings are also likely to be published quicker than negative ones. As a consequence, bias is introduced: results from published ...

  14. Judging the relative trustworthiness of research results: How to do it

    Or in an experiment where participants dropped out once they had been allocated to a treatment group. In all of these examples, and many others, the missing data creates the potential for considerable bias in the study results (Gorard, 2020). In summary, if all other factors including the number of cases remain the same, then a study with less ...

  15. Bias in research

    Bias in research can cause distorted results and wrong conclusions. Such studies can lead to unnecessary costs, wrong clinical practice and they can eventually cause some kind of harm to the patient. It is therefore the responsibility of all involved stakeholders in the scientific publishing to ensure that only valid and unbiased research ...

  16. Research bias: What it is, Types & Examples

    Research bias: What it is, Types & Examples. The researcher sometimes unintentionally or actively affects the process while executing a systematic inquiry. It is known as research bias, and it can affect your results just like any other sort of bias. When it comes to studying bias, there are no hard and fast guidelines, which simply means that ...

  17. PDF Bias in research

    Table 1 Types of research bias Design bias Poor study design and incongruence between aims and methods increases the likelihood of bias. For example, exploring HIV testing using a survey is unlikely to obtain in-depth ... which may bias the findings towards more favourable results. Confounding bias can also occur because of an association ...

  18. [Three types of bias: distortion of research results and how ...

    Abstract. A systematic distortion of the relationship between a treatment, risk factor or exposure and clinical outcomes is denoted by the term 'bias'. Three types of bias can be distinguished: information bias, selection bias, and confounding. These three types of bias and their potential solutions are discussed using various examples.

  19. Types of Bias in Research

    Confirmation bias is the tendency to seek out information in a way that supports our existing beliefs while also rejecting any information that contradicts those beliefs. Confirmation bias is often unintentional but still results in skewed results and poor decision-making. Example: Confirmation bias in research.

  20. Understanding Different Types of Research Bias: A Comprehensive Guide

    Research bias is the tendency for qualitative and quantitative research studies to contain prejudice or preference for or against a particular group of people, culture, object, idea, belief, or circumstance. Bias is rarely based on observed facts. In most cases, it results from societal stereotypes, systemic discrimination, or learned prejudice ...

  21. Illuminating 'the ugly side of science': fresh incentives for reporting

    Over the past 30 years, the proportion of negative results being published has decreased further. A 2012 study showed that, from 1990 to 2007, there was a 22% increase in positive conclusions in ...

  22. Implicit Bias Hurts Everyone. Here's How to Overcome It

    Oftentimes if certain concepts are more closely paired in your mind, then it will be easier for you to make that association. Your response will be faster. When the pairing is less familiar to you ...

  23. Reducing bias and improving transparency in medical research: a

    This results in a distortion of the published record which disproportionately features findings that are deemed to be novel, striking or that provide evidence in favour of a proposed intervention. 26 While publication bias is commonly understood to be driven by the perception that journals are unlikely to accept so-called 'negative' or ...

  24. How Researcher Bias Affects Qualitative Reliability

    Peer review is a critical mechanism for reducing the impact of researcher bias. By having other experts evaluate the research design, data collection methods, and interpretation of results, you ...

  25. Managing Research Bias in Business Management

    In the realm of business management, conducting research is pivotal for informed decision-making. However, biases in research design can significantly skew results, leading to poor business ...

  26. What Is Selection Bias?

    Revised on May 1, 2023. Selection bias refers to situations where research bias is introduced due to factors related to the study's participants. Selection bias can be introduced via the methods used to select the population of interest, the sampling methods, or the recruitment of participants. It is also known as the selection effect.

  27. 4 Simple Interventions To Reduce Biases Against Women At Work

    Explore research-based strategies for combating gender discrimination: Tweaks in recruiting selection and promotion processes can reduce the impact of implicit bias. ... This results in male-heavy ...

  28. Gender gaps in mathematics and language: The bias of competitive

    This research paper examines the extent to which high-stakes competitive tests affect gender gaps in standardized tests of Mathematics and Language. To this end, we estimate models that predict students' results in two national standardized tests: a test that does not affect students' educational trajectory, and a second test that determines access to the most selective universities in Chile.

  29. Dealing with the positive publication bias: Why you should really

    Publication bias is recognized by research funders that consider publishing negative results should be a priority . The effects of publication bias have not gone unnoticed among scientists and clinicians as they reported in an online survey that nearly 70% of researchers were unable to reproduce published results . Because of a high rate of ...