"Free Testing and PrEP without Outing Myself to Parents:" Motivation to participate in oral and injectable PrEP clinical trials among adolescent men who have sex with men.

Results suggest future biomedical HIV prevention research will need to develop procedures to address AMSM's confidentiality concerns, enhance youth's understanding of random assignment, the continued importance of medication adherence and partner condom use during trial participation, and availability of alternative sexual health services to avoid the potentially undue influence of access to free sexual health services.