The (Mis)Reporting of Male Circumcision Status among Men and Women in Zambia and Swaziland: A Randomized Evaluation of Interview Methods

BACKGROUND: To date, male circumcision prevalence has been estimated using surveys of men self-reporting their circumcision status. HIV prevention trials and observational studies involving female participants also collect data on partners' circumcision status as a risk factor for HIV/STIs. A number of studies indicate that reports of circumcision status may be inaccurate. This study assessed different methods for improving self- and partner reporting of circumcision status. METHODS/FINDINGS: The study was conducted in urban and rural Zambia and urban Swaziland. Men (N = 1264) aged 18–50 and their female partners (N = 1264), and boys (N = 840) aged 13–17 were enrolled. Participants were recruited from HIV counseling and testing sites, health centers, and surrounding communities. The study experimentally assessed methods for improving the reporting of circumcision status, including: a) a simple description of circumcision, b) a detailed description of circumcision, c) an illustration of a circumcised and uncircumcised penis, and d) computerized self-interviewing. Self-reports were compared to visual examination. For men, the error in reporting was largely unidirectional: uncircumcised men more often reported they were circumcised (2–7%), depending on setting. Fewer circumcised men misrepresented their status (0.05–5%). Misreporting by women was significantly higher (11–15%), with the error in both directions. A sizable number of women reported that they did not know their partner's circumcision status (3–8%). Computerized interviewing did not improve accuracy. Providing an illustration, particularly for illiterate participants, significantly improved reporting of circumcision status, decreasing misreporting among illiterate participants from 13% to 10%, although misreporting was not eliminated. CONCLUSIONS: Study results suggest that the prevalence of circumcision may be overestimated in Zambia and Swaziland; the error in reporting is higher among women than among men. Improved reporting when a description or illustration is provided suggests that the source of the error is a lack of understanding of male circumcision.