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Specific categories of healthy participants – guidance

Guidance involving specific categories of healthy participants such as students, employees or prisoners.

Types of specific categories

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Universities and other training institutions provide investigators with a ready 'pool' of study participants: students.


There is a possibility that students will not be agreeing to participate in a study freely. Students may volunteer to participate in the belief that doing so will place them in good favour with academic staff (ie, will result in better grades, recommendations or employment, etc) or that failure to participate will negatively affect their careers.

Prohibiting all student participation in research would be too extreme. One way to protect against coercion is to advertise for participants generally (eg, through notices posted around the campus or department) rather than recruit individual student participants directly.


Maintaining confidentiality is another concern. Studies that involve sensitive topics, such as mental health, sexual activity or the use of illicit drugs or alcohol, presents risks for participant confidentiality.

The close environment of training institutes amplifies this problem. All participants should be made aware of and protected from such risks as much as possible.


Drug company employees are often seen as ideal participants in studies because they understand the study’s protocol and importance more readily. However, the risks for employee study participants are similar to those for students: coercion and breaching confidentiality.

Employees may agree to participate in a study in the belief that doing so will affect performance evaluations or job advancement.

It may also be difficult to maintain the confidentiality of personal medical information or study data when the participants are also employees; particularly when the employer is a medical institution.

Prison inmates and other captive populations

Prisons used to be attractive environments for studies seeking participants because of the stability of inmate life (controlled diet, ready availability of participants for follow up).

However, the very fact of incarceration can make it difficult or impossible for inmates to give voluntary, informed consent to participate in a study.

To the extent that inmates can voluntarily consent to participate, and are able to under applicable regulations, they should be allowed to participate in potentially beneficial studies.

Issues to consider:

Choice of participant:

  • Has the prison population been chosen simply because it is a stable, static population that is convenient to use?

Use of data:

  • Can data on the prison participants be kept confidential?
  • When inmates are moved around (for example, to go to a study appointment), everyone knows about it.
  • Prison records, including medical records, are accessible to people who, in other settings, would not have access to such personal information – for example, inmates participating in HIV-related research. Investigators must be able to ensure that they can and will maintain the necessary confidentiality for their study participants.

Coercion or undue influence:

  • Prisons create environments in which the offer to participate in a study is coercive or can create an undue influence.
  • For example, the investigator may propose to move study participants to a special unit where they will be given medical care with better living conditions than those provided to the general prison population. Even the opportunity to leave the prison cell and interact with people from outside the prison may act as an undue inducement to participate in a study.

Burden or benefits:

  • Involving inmates in a study raises questions of burden and benefit. Inmates should neither bear an unfair share of the burden of participating in the study nor be excluded from its benefits.

For more information

For more information, refer to the NEAC Guidelines for Intervention Studies: Appendix 2.