Background: Unprotected receptive anal sex is one of the highest risk factors for HIV infection. In vaginal microbicide trials, anal sex also threatens to undermine measurement of product efficacy. However, collecting reliable data on anal sex is difficult, since in many cultures, it is taboo. We describe the contribution of qualitative methods to assessing norms of anal sex within trial communities. Methodology: In-depth interviews (IDIs) were conducted with a random sub-sample of 464 women in the MDP301 Phase III vaginal microbicide trial. Focus group discussions (FGDs) were also conducted with male and female community members not enrolled in the trial. Anal sex was discussed using open questions and transcripts were analysed thematically. Information was compared to quantitative data collected on clinic questionnaires. Results: Very few women reported having anal sex, both on quantitative and qualitative tools. However, IDIs and FGDs provided a rich discourse of community norms around anal sex, its acceptability, scenarios of occurrence and reported prevalence. There was wide country variation in these discourses; in urban South Africa, many more women had tried anal sex or knew others who were practising it. In contrast, in rural Uganda and Zambia, discussion was short-lived - anal sex was said to be practised only by ‘deviant others', such as prisoners and rapists. Whilst these qualitative data cannot be transformed into numbers, they provide evidence of more anal sex than the quantitative data suggest, and reveal sexual behaviour norms which support higher estimates in some contexts. Conclusions: Reliable data on anal sex is important for interpreting multi-site microbicide trial results. A combination of qualitative interviewing and FGDs can provide access to more hidden information on this taboo subject and reveal wider cultural norms and discourses in which it is embedded, thus helping trialists bracket the level of confidence placed in self-reported behaviour questionnaires.
Montgomery, C.M. Capturing heterosexual anal sex in a phase III vaginal microbicide trial: using qualitative methods to understand community norms. Presented at Microbicides 2008, New Delhi, India, 24-27 February 2008. (2008)