Bias Analysis of Self-Reporting of Sexually Transmitted Infections Symptoms in Face-to-Face Interviews with Women in Kerman, Iran

Asking about sexually transmitted infections (STIs) symptoms through face-to-face interviews (FTFI) or self-administered questionnaire (SAQ) is one way to indirectly estimate the prevalence of STIs in the general population. The aim of the present study was to investigate self-report bias of STIs symptoms via FTFI in comparison with SAQ.
This cross-sectional study was conducted in 2013. Using a multi-stage sampling method, 496 were selected from among women living in Kerman. From among the participants, 248 filled out a standardized questionnaire containing 12 questions about experience of STIs symptoms at the time of the study (current) and the preceding six months (recent). Moreover, the rests of the subjects (n = 248) answered those questions through FTTI. Descriptive analysis, logistic regression, and odds ratio (OR) were used to analyze data considering the significance level of 5%.
Findings: OR of self-reporting of current STIs symptoms in FTFI was 23% less than SAQ (P = 0.001), while OR of self-reporting of recent STIs symptoms by FTFI was 26% more than SAQ (P = 0.001). This trend persisted after adjusting confounders’ effects. Educational level had more contribution in increasing OR of self-reporting in SAQ compared to FTFI (OR = 1.34).
It seems that FTFI does not always cause bias in self-reporting of STIs symptoms; it depends on the time of experience of STIs (current or recent). However, in interpreting the results, a greater consideration of the weakness of both FTFI and SAQ which may be biased in reporting is recommended.