Vulnerable Groups

Vulnerable groups involve human samples considered particularly susceptible to coercion or undue influence in a research setting. A vulnerable group includes persons who may be incapable of understanding what it means to participate in research and/or who may not understand what constitutes informed consent. Individuals considered vulnerable may, for various reasons, have a diminished capacity to anticipate, cope with, resist, and/or recover from the impact of a natural or man-made hazard. Vulnerable groups may also consist of individuals who are unable to care for themselves and/or may have an increased chance of suicide, self-harm, or the likelihood of harming others.

Researchers’ assignment of vulnerable group status is both dynamic and relative, because the nature of those groupings is culturally dependent and those labeled as vulnerable are perceived as being in danger, at risk, under threat, susceptible to problems, helpless, and/or in need of protection or support. A situation that makes one person vulnerable may not make another person vulnerable. Being identified as a vulnerable group participant may also overlap with being identified as a victim or a troubled or troublesome individual.

Groups considered vulnerable can vary across academic disciplines, based on the frequency of practitioners’ or researchers’ interactions with those characteristics being studied. However, a nonexhaustive list of groups considered vulnerable across many human-research fields include children, the elderly, single parents, people with disabilities, ethnic minorities, those who are mentally disabled, asylum seekers and refugees, prisoners, pregnant women and fetuses, addicts, individuals with little social support, patients with an acute illness or chronic pain, victims of intimate and other forms of violence, and those who are homeless, economically disadvantaged, poor, illiterate, or unemployed. Some scholars argue that even students used as study participants are vulnerable if their research participation in a specific study (without reasonable alternatives) is mandatory for class credit.

This entry discusses the types of vulnerable groups, provides examples of inappropriate handling of vulnerable groups for research, and [Page 1871]presents guidelines for protecting vulnerable groups during research studies.