Which of the following statements about IRB composition is true?

• A. Only physicians may serve
• B. At least five members with diversity including at least one scientific member, at least one non-scientific member, and at least one not affiliated with the institution
• C. A majority must be external to the institution
• D. Members must all be affiliated with the hospital

Answer: (B)

The important idea is how IRBs are designed to review human subjects research: they must include a diverse mix of members to provide broad perspectives, expertise, and independence. Federal rules require at least five members with backgrounds that cover scientific and non-scientific areas, and at least one member who is not affiliated with the institution. This combination ensures the IRB has the necessary technical insight, a non-scientific viewpoint, and external independence to guard against conflicts of interest. That’s why the statement describing a minimum of five members with both scientific and non-scientific representation, plus at least one unaffiliated member, is correct. It’s not about a physician-only group, a majority of external members, or all members being affiliated with the hospital; those conditions aren’t required and, in fact, would violate the regulations.