Fig. 1.

Flow chart of participant enrollment, survey distribution, and response rates. The target sample size for this study was 100. Study staff approached Partners PrEP clinical trial participants for enrollment during their monthly clinic visits. Some participants had already completed maximum follow-up for the Partners PrEP Study clinical trial at the time this pilot evaluation was conducted. A total of 110 participants were enrolled in the study, of which 96 participants responded to ≥5 of 7 daily surveys during the 1st week run-in. Of 5,760 surveys planned for 96 participants over 60 days, 5,412 surveys were distributed, 32 surveys were cancelled after one participant exited due to pregnancy, and 316 surveys were not delivered due to a mid-study block by a local mobile phone provider