Attitudes towards participating in research involving digital pill systems to measure oral HIV pre-exposure chemoprophylaxis: a cross-sectional study among men who have sex with men with substance use in the USA.

Objectives: This quantitative survey sought to understand, among men who have sex with men (MSM) with potentially problematic substance use, the attitudes towards participation in research involving digital pill systems (DPS) for HIV pre-exposure prophylaxis (PrEP) adherence measurement, and the barriers and facilitators to research participation.

Design: One-time, cross-sectional, online sampling-based survey.

Setting: US social networking app predominantly focused on MSM.