Under 45 CFR 46, vulnerable populations include individuals who may be susceptible to coercion, undue influence, or who have limited ability to provide informed consent. Examples include:

• Children
• Prisoners
• Pregnant women, fetuses, and neonates
• Individuals with impaired decision-making capacity
• Economically or educationally disadvantaged persons
• Individuals dependent on the researcher (students, employees, patients)

All recruitment of vulnerable populations must:

• Be voluntary and free from coercion or undue influence
• Use clear, understandable, non-exculpatory language
• Avoid overstating benefits or minimizing risks
• Clearly state that participation is optional
• Use reasonable compensation that is not coercive
• Include additional safeguards when appropriate
• Be reviewed and approved by the IRB before distribution

Children are persons who have not reached the legal age of consent.

Requirements

• Parental permission is required.
• Child assent must be obtained when developmentally appropriate.
• Risk level must fall into a category permitted under Subpart D.
• Recruitment materials must be written for both parents and children.
• No language implying obligation or authority (e.g., “your doctor wants you to…”).

Prisoners are considered vulnerable due to restricted autonomy.

Requirements

• Research must fall into permitted categories under Subpart C.
• Participation must not affect parole, privileges, or treatment.
• Recruitment must be free from real or perceived pressure.
• A prisoner representative must participate in IRB review.
• Incentives must be carefully reviewed to avoid undue influence.

(Subpart B – 45 CFR 46.201–207)

Requirements

• Risks to the pregnant individual and fetus must be minimized.
• Consent requirements depend on study design and potential benefit.
• Recruitment materials must clearly describe:
  • Purpose of the research
  • Potential risks and benefits
  • Available alternatives
• Studies must meet Subpart B conditions before approval.

This includes people with cognitive, developmental, psychiatric, or neurological conditions.

Safeguards May Include:

• Use of legally authorized representatives (LARs)
• Consent monitoring
• Comprehension checks
• Simplified consent forms
• Independent advocates

Recruitment must not exploit authority, dependency, or financial need.

Examples of inappropriate practices:

• Recruiting students by their own instructor
• Offering excessive payment to economically disadvantaged participants
• Implying participation is required for services or benefits

All of the following must be reviewed and approved before use:

• Flyers, advertisements, emails, social media posts
• Scripts for verbal recruitment
• Letters, phone scripts, or referrals
• Compensation plans

• Use plain language and culturally appropriate materials
• Provide adequate time to consider participation
• Offer opportunities to ask questions
• Separate research recruitment from clinical or authority roles when possible
• Consult the HRPP early when planning recruitment

Contact the HRPP for:

• Recruitment planning guidance
• Consent strategy support
• Regulatory clarification
• Study-specific consultation