Overestimating HIV Infection: The Construction and Accuracy of Subjective Probabilities of HIV Infection in Rural Malawi

Philip A. Anglewicz, University of Pennsylvania

In the absence of testing, how accurate are rural Malawians in assessing their HIV status? In this paper, I use a unique dataset that includes respondents’ HIV status as well as their subjective likelihood of HIV infection. These data show that many men and women in rural Malawi overestimate their likelihood of current HIV infection. This difference between self-assessed and objective HIV status raises an important question: why are so many wrong? I begin by identifying characteristics of individuals associated with the belief that they are, or are not, already infected. I then compare subjective probability of infection with biomarker results, to find what proportion of the respondents accurately identifies their HIV status. Next, I distinguish between those who overestimate their risk and those who underestimate it, and ask what characteristics of individuals are associated with these errors. Finally, I discuss the implications of incorrect perceived HIV status.