Methods to reduce social desirability bias in sex surveys in low-development settings: Experience in Zimbabwe

Background: Social desirability bias hampers measurement of risk behavior for acquiring STDs and evaluation of control interventions. More confidential data collection methods reduce this bias in Western countries but generally require technology not available in less developed settings. Goal: The goal of this report was to describe and evaluate an informal, confidential, low-technology method-Informal Confidential Voting Interviews (ICVIs)-for collecting sexual behavior data in less developed settings. Study Design: Reports of multiple sex partners by sexually active, basic-literate, population-based survey participants in rural Zimbabwe randomly assigned to ICVIs and face-to-face interviews (FTFIs) were compared. Results: Ninety-two percent of respondents (n = 7823) were sufficiently literate for ICVIs. Error rates were low but higher than in FTFIs. More male and female ICVI respondents interviewed reported multiple current sex partners (OR = 1.33 and 5.24, respectively) and multiple partners in the past month (OR = 1.71 and 2.92) and the past year (OR = 1.35 and 1.97). Conclusion: The ICVI method appears to reduce bias but requires further evaluation to assess viability and effect in alternative settings.