What is the minimum number of IRB/IEC members recommended?

• A. Three
• B. Five
• C. Seven
• D. Nine

Answer: (D)

The key idea here is how an IRB/IEC should be composed to ensure proper oversight. To provide balanced review, an IRB must include enough members to cover different perspectives and maintain independence. The minimum number needed to achieve this is five, which allows for essential roles such as at least one member not affiliated with the institution and at least one member whose primary concerns are in nonscientific areas, while still having other members with scientific or clinical expertise. Having fewer than five would make it hard to guarantee these diverse viewpoints and independence. While IRBs can have more than five, the question asks for the minimum, which is five. Nine is not the minimum; it’s simply a larger board, which some institutions may choose, but it isn’t the required minimum.