Self-reported male circumcision (MC) status is frequently used to estimate MC prevalence, although its accuracy varies by setting. Nevertheless, self-reported MC status remains essential because it is the most feasible method of collecting MC status data in community surveys; and its accuracy is an important determinant of data reliability. We assessed the accuracy of self-reported MC status among adult men during a household survey in non-circumcising communities within Nyanza region of Kenya where MC for HIV prevention is being rolled out.
A total of 5,656 men aged 25-39 years from four counties were enrolled and a baseline questionnaire that captured information on self-reported MC status administered to 4,232 consenting men. Thereafter, a trained research assistant physically verified their MC status as fully circumcised (no foreskin), partially circumcised (foreskin is past coronal sulcus but covers less than half of the glans) or uncircumcised (foreskin covers half or more of the glans). The sensitivity and specificity of self-reported MC status were calculated using physically verified MC status as the gold standard. The data were pooled for analysis and did not account for the study design.
Out of 4,232 men, 2,197 (51.9%) reported being circumcised of whom 99.0% (2,176/2,197) were confirmed as fully circumcised on physical examination. Among the 2,035 men who reported being uncircumcised, 93.7% (1,907/2,035) were confirmed uncircumcised by physical examination. Kappa agreement between self-reported and physically verified MC status was high, К= 0.9858 (95% CI, 0.981-0.991), p<0.001. The sensitivity of self-reported MC status was 99.59% and specificity was 98.97%, and did not differ significantly by age group; the sensitivity range was 99.3% – 99.6%, and the specificity range was 98.7 % – 99.6%. Similarly, the Kappa agreement was high for all age groups: range 0.9805 – 0.9917.
In this study population, the accuracy of self-reported MC status was high at 99.0%; therefore in this setting MC coverage estimates based on self-reported MC status are accurate and applicable for planning. We recommend similar studies to validate accuracy of self-reported MC status in other populations where MC is being rolled out.