The validity of self-reported likelihood of HIV infection among the general population in rural Malawi

Background: Understanding HIV risk perception is important for designing appropriate strategies for HIV/ AIDS prevention, because these interventions often rely on behaviour modification. A key component of HIV risk perception is the individual's own assessment of HIV status, and the extent to which this assessment is correct. However, this issue has received limited attention. Objectives: To examine the validity of self-reported likelihood of current HIV infection among the general population in rural Malawi. Methods: As part of a panel household survey, data on behaviour and biomarkers were collected for a population-based sample of approximately 3000 respondents in rural Malawi aged >= 15 years. Information on self-assessed likelihood of currently having HIV was collected by survey interview. Saliva was obtained from all consenting respondents to assess actual HIV status. Results: Of 2299 survey respondents who assessed their likelihood of being infected with HIV at the time of the survey, 71% were accurate. Most incorrect assessments (88%) were due to respondents overestimating (rather than underestimating) their likelihood of being infected with HIV. Women were less likely than men to correctly assess their HIV status. The two most important predictors of false-positive responses were marital status and self-reported health. Conclusions: Self-reports of HIV infection were generally valid. Most invalid self-reports were due to overestimating the risk of having HIV. The implications of this finding are highlighted, as they pertain to the design of HIV prevention interventions and the expansion of HIV counselling, testing and treatment programmes in developing countries.