Oximately 15 participants per group, per site. During the SSIs, participants viewed

Oximately 15 participants per group, per site. During the SSIs, participants viewed a graph displaying their composite adherence scores over the 13 study visit intervals as a discussion aid (Fig 1). Only participants in the high and moderate groups were asked to describe reasons why they adhered to the study pill regimen. We first asked a broad question to participants in the high adherence group: “What made it easy for you to take the study pills?” After responding to the question, participants were asked direct probes about other potential reasons, to explore whether any of those other factors contributed to their adherence. The probes included perceived HIV risk, belief that the pill was efficacious for HIV prevention, and partner support. Before moving to the next section, participants were asked an indirect probe to identify any other possible reasons for taking the study pill. Participants in the moderate group were asked about what led them to take the study pill some of the time but not all of the time and about times during the trial when they took the study pill more often. Follow-up probes were asked that focused on potential events or experiences that might have motivated adherence, such as engaging in perceived risky sexual behavior, being unsure of partners’ HIV status, and receiving adherence counseling; an indirect probe was also asked to explore other possible reasons. Personalized questions were asked to fpsyg.2014.00822 participants in both the high and moderate group when appropriate (e.g., the participant had fluctuating adherence composite scores) fpsyg.2016.00135 to specifically probe about the context surrounding the participant’s individual adherence patterns. Participants in the none/scarce group were not asked questions on reasons they may have taken the study pill at times. Instead, they were asked to describe what they believed made it possible for other FEM-PrEP participants to take the study pill some or most of the time, as well as about times during the trial when other participants were able to take the study pill more often. Participants in the moderate and high groups were also asked these questions. A quantitative, audio computer-assisted self-interview (ACASI) was offered to all former FEM-PrEP participants who participated in the larger follow-up study. ACASI was completed by 1) participants from the three SSI adherence groups described above (i.e., high, moderate, and none/scarce), 2) participants assigned placebo during FEM-PrEP, and 3) former FEMPrEP participants who participated in a separate SSI on risk perceptions. Details regarding the eligibility criteria and recruitment of these populations have been described elsewhere [14]. We chose to gather data using ACASI, in addition to SSIs, because ACASI can potentially reduce socially desirable responses [15] and because previous FEM-PrEP findings showed thatPLOS ONE | DOI:10.1371/purchase Serabelisib journal.pone.0125458 April 13,4 /Facilitators of Study Pill Adherence in FEM-PrEPFig 1. Example of adherence composite score graph shown to participants. doi:10.1371/journal.pone.0125458.gparticipants over-reported their adherence in the interviewer-administered quantitative Biotin-VAD-FMK web surveys and SSIs conducted during the clinical trial [12]. All participants were informed that their ACASI answers would not be linked to them or to their demographic information, to further reduce the likelihood of social-desirability bias. During ACASI, participants were asked to think about the study pills that they took during t.Oximately 15 participants per group, per site. During the SSIs, participants viewed a graph displaying their composite adherence scores over the 13 study visit intervals as a discussion aid (Fig 1). Only participants in the high and moderate groups were asked to describe reasons why they adhered to the study pill regimen. We first asked a broad question to participants in the high adherence group: “What made it easy for you to take the study pills?” After responding to the question, participants were asked direct probes about other potential reasons, to explore whether any of those other factors contributed to their adherence. The probes included perceived HIV risk, belief that the pill was efficacious for HIV prevention, and partner support. Before moving to the next section, participants were asked an indirect probe to identify any other possible reasons for taking the study pill. Participants in the moderate group were asked about what led them to take the study pill some of the time but not all of the time and about times during the trial when they took the study pill more often. Follow-up probes were asked that focused on potential events or experiences that might have motivated adherence, such as engaging in perceived risky sexual behavior, being unsure of partners’ HIV status, and receiving adherence counseling; an indirect probe was also asked to explore other possible reasons. Personalized questions were asked to fpsyg.2014.00822 participants in both the high and moderate group when appropriate (e.g., the participant had fluctuating adherence composite scores) fpsyg.2016.00135 to specifically probe about the context surrounding the participant’s individual adherence patterns. Participants in the none/scarce group were not asked questions on reasons they may have taken the study pill at times. Instead, they were asked to describe what they believed made it possible for other FEM-PrEP participants to take the study pill some or most of the time, as well as about times during the trial when other participants were able to take the study pill more often. Participants in the moderate and high groups were also asked these questions. A quantitative, audio computer-assisted self-interview (ACASI) was offered to all former FEM-PrEP participants who participated in the larger follow-up study. ACASI was completed by 1) participants from the three SSI adherence groups described above (i.e., high, moderate, and none/scarce), 2) participants assigned placebo during FEM-PrEP, and 3) former FEMPrEP participants who participated in a separate SSI on risk perceptions. Details regarding the eligibility criteria and recruitment of these populations have been described elsewhere [14]. We chose to gather data using ACASI, in addition to SSIs, because ACASI can potentially reduce socially desirable responses [15] and because previous FEM-PrEP findings showed thatPLOS ONE | DOI:10.1371/journal.pone.0125458 April 13,4 /Facilitators of Study Pill Adherence in FEM-PrEPFig 1. Example of adherence composite score graph shown to participants. doi:10.1371/journal.pone.0125458.gparticipants over-reported their adherence in the interviewer-administered quantitative surveys and SSIs conducted during the clinical trial [12]. All participants were informed that their ACASI answers would not be linked to them or to their demographic information, to further reduce the likelihood of social-desirability bias. During ACASI, participants were asked to think about the study pills that they took during t.