Preventive Misconception and Risk Behaviors in a Multinational HIV Prevention Trial.

Background: Some HIV prevention research participants may hold a "preventive misconception" (PM), an overestimate of the probability or level of personal protection afforded by trial participation. However, these reports typically rely upon small, retrospective qualitative assessments that did not use a standardized approach.

Methods: We administered a measure of PM called PREMIS, during Microbicide Trials Network 020-A Study to Prevent Infection with a Ring for Extended Use, a large, multicenter, placebo-controlled, phase III trial evaluating the safety and efficacy of a dapivirine vaginal ring among women at risk for HIV infection in Malawi, South Africa, Uganda, and Zimbabwe. The maximum follow-up period was 2.6 years.

Results: One thousand two hundred sixty-one respondents completed PREMIS at their month 3 visit (M3); 2085 at their month 12 visit (M12); and 1010 at both visits. Most participants expressed high expectations of personal benefit (EPB) and that at least one of the rings used in the trial would reduce the risk of getting HIV (expectation of maximum aggregate benefit or EMAB). There was a moderate positive correlation between EPB and EMAB at M3 (r = .43, 95% CI: .37, .47) and M12 (r = .44, 95% CI: .40, .48). However, there was variability among sites in the strength of the relationship. There was no relationship between either expectation variable and condom use, adherence, or HIV infection.

Conclusions: A majority of trial participants expressed some belief that their risk of HIV infection would be reduced by using a vaginal ring, which may signal PM. However, such beliefs were not associated with adherence, condom use, or subsequent HIV infection, and there was variability across sites. Further work is needed to understand these findings.