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 ...