Over-reporting in handwashing self-reports: potential explanatory factors and alternative measurements

Abstract

Handwashing effectively prevents from several communicable diseases. Handwashing interventions are a program priority in development aid. Intervention evaluations are rare because handwashing is difficult to measure with observations being valid but costly and self-reports being efficient but invalid due to over-reporting (OvR). While socially desirable responding (SDR) is claimed as the main cause of OvR, the underlying factors are understudied. We investigated factors potentially explaining over-reported handwashing to gain indications for measures mitigating OvR. One alternative self-report measure was developed and tested. Data were collected cross-sectionally in Ethiopia, by observations and interviews (N = 554). Correlation and regression analyses and dependent t-tests were conducted. OvR was associated with factors potentially involved in SDR; encoding and recall of information and dissonance processes. The latter two factor groups explained OvR beyond SDR. The alternative self-report measure reduced OvR when compared to conventional self-reports. The present study is the first investigating factors explaining over-reported handwashing. It contributes to a limited evidence base on a highly important subject: how to evaluate handwashing interventions efficiently and accurately.