Definition of Vulnerable subjects can refer to ICH GCP R2 1.61 （including hierarchy relationship）. 不过这个问题是说弱势群体能否参加临床试验，及如何体现特殊保护。

GCP 没有禁止弱势群体参加试验，对于弱势群体的保护，是IRB 职责的一部分，ICH GCP 3.1.1 An IRB/IEC should safeguard the rights, safety, and well-being of all trial subjects. Special attention should be paid to trials that may include vulnerable subjects.