The Many Faces of “Coercion” and “Undue Influence”

The United States regulations governing research with humans pay special attention to two ethical concepts that may not be familiar from everyday life: “coercion” and “undue influence.” These concepts appear in the section of the regulations that address informed consent, where investigators are instructed “to seek consent only under such circumstances…that minimize the possibility of coercion and undue influence” (21 CFR 50.20). These concepts also surface in IRB review of research involving vulnerable populations, where the regulations enjoin IRBs to apply additional safeguards for populations that “are likely to be vulnerable to coercion or undue influence” (21 CFR 56.111).

Despite the regulatory importance of these concepts, there is wide variation in how they are understood and applied by IRBs in practice. Coercion and undue influence in research can take many forms, and it is important not only to be clear about what these ideas mean in the abstract but to also have a sense of what does, and what does not, count as concrete cases of coercion or undue influence. This permits IRBs to identify situations involving heightened risks of coercion and undue influence and apply reasonable protections consistently.

What Are “Coercion” and “Undue Influence”?

The regulatory emphasis on “coercion” and “undue influence” originates with the Belmont Report, which many take to be the founding document of the US regulatory framework. The Belmont Report defines “coercion” as occurring “when an overt threat of harm is intentionally presented by one person to another in order to obtain compliance.”

By contrast, “‘undue influence” is defined as occurring “through an offer of an excessive, unwarranted, inappropriate, or improper reward or other overture to obtain compliance.” Notably, the US Office for Human Research Protections (OHRP) adopts very similar definitions in their Informed Consent FAQs.

Both coercion and undue influence are ethically inappropriate ways of interacting with research participants, typically with the goal of influencing them to enroll or remain in studies. The main difference between the concepts is that coercion involves a threat of something bad, to harm another or violate their rights, whereas undue influence involves an inappropriate enticement with something seen as good.

Faces of Coercion

Historically, the main examples of coercion in research involve scandal and atrocities, such as individuals literally being forced to participate in research against their will, as occurred with experiments conducted by the Nazis during World War II. Today, such egregious cases of coercion are rare, and the regulations apply stringent criteria to areas of research where there may be the most risk for blatant coercion, such as research involving prisoners. At the same time, coercion can manifest itself in more subtle ways.

For example, imagine a professor doing survey research about sensitive and private topics who wishes to use their students as participants, and who threatens to fail or penalize any students who do not complete the survey.

Similarly, imagine a physician-researcher who threatens to withhold access to some service or product (for example, a limited drug for treating COVID-19) unless their patient participates in a research study that they are conducting.

Finally, consider a situation where an investigator threatens to pay a participant less than was promised at initial consent unless they continue into a distinct extension study, despite the fact that the participant has adhered to all study requirements and met the stated conditions on receiving the full payment amount.

Each of these plausibly counts as a case of coercion, involving threats of something bad or unfair, or to withhold something participants have a right to, if participants do not act as desired. While not as egregious as the Nazi experiments, cases like these—which often involve situations where there are stark power differentials between researchers and participants—nonetheless merit IRB concern and proactive safeguards.

Faces of Undue Influence

IRBs will perhaps be most familiar with undue influence as it arises in discussions of payment for research participation, which undeniably involves the offer of something seen as good (money) and may have the effect of motivating people to enroll or remain in studies. However, similar concerns may also arise when the offer of any good or benefit, not just money, is used to motivate research enrollment.

For example, concerns about undue influence would arise for a professor who offered to write glowing letters of recommendation for any students that complete their survey research, as well as for physicians who offered special services or benefits (say, access to single-bed “VIP” hospital rooms for life) for patients who enroll in their trial.

Assessing whether offers of benefit in fact count as undue influence and deserve protective responses from the IRB is notoriously difficult. Importantly, the definition of “undue influence” found in the Belmont Report as well as regulatory guidance on this issue distinguish appropriate from inappropriate benefits offered to participants. The mere fact that a benefit is offered is not ethically concerning, even if that benefit motivates participation. What is concerning is when an offer of benefit is so excessive or enticing that it compromises evaluation of the risks or otherwise clouds participant understanding to the point where the legitimacy of their informed consent is put in doubt.

Knowing where to draw the line between appropriate and inappropriate incentives is a challenge for IRBs and the research community generally. Because different benefits, such as payment amounts, impact people differently, it may often be wise to address the underlying concern with preserving the integrity of informed consent in these situations—through mechanisms such as comprehension checks and in-depth review of consent materials and risks with participants by the research team—before imposing unduly heavy-handed restrictions on the provision of payment and other benefits for participation.

Want to find out more about coercion and undue influence during informed consent? Watch our free webinar Evaluating Payment to Participate in Research: Ethical and Regulatory Issues.

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