Studies assessing risk of sexual behavior and disease are often plagued by questions about the reliability of self-reported sexual behavior. In this study, we evaluated the reliability of self-reported sexual history among urbanized women in a prospective study of cervical HPV infections in Nigeria.
We examined test–retest reliability of sexual practices using questionnaires administered at study entry and at follow-up visits. We used the root mean squared approach to calculate within-person coefficient of variation (CVw) and calculated the intra-class correlation coefficient (ICC) using two way, mixed effects models for continuous variables and
We found that self-reported sexual history was generally reliable, with overall ICC ranging from 0.7 to 0.9; however, the reliability varied by nature of sexual behavior evaluated. Frequency reports of non-vaginal sex (agreement = 63.9%, 95% CI: 47.5–77.6%) were more reliable than those of vaginal sex (agreement = 59.1%, 95% CI: 55.2–62.8%). Reports of time-invariant behaviors were also more reliable than frequency reports. The CVw for age at sexual debut was 10.7 (95% CI: 10.6–10.7) compared with the CVw for lifetime number of vaginal sex partners, which was 35.2 (95% CI: 35.1–35.3). The test–retest interval was an important predictor of reliability of responses, with longer intervals resulting in increased inconsistency (average change in unreliability for each 1 month increase = 0.04, 95% CI = 0.07–0.38,
Our findings suggest that overall, the self-reported sexual history among urbanized Nigeran women is reliable.