Wealth-related inequalities in handwashing with water and soap at critical times among mothers/caregivers of children under-five years in rural Afghanistan: a decomposition analysis

Handwashing with water and soap is a fundamental preventive behaviour, yet substantial socio-economic inequalities shape hygiene practices. This study assessed the magnitude and determinants of inequalities in reported handwashing behaviour among households in Afghanistan. Inequality was examined using concentration curves and concentration indices, while the Erreygers decomposition method was employed to identify the contributions of socio-demographic factors to socio-economic gradients in handwashing. Data were obtained from 1,208 households participating in baseline (March 2022) and endline (December 2022) surveys. The outcome was reported as handwashing with water and soap at least three times per day. Concentration indices quantified inequality, and Erreygers decomposition assessed factor contributions. Pro-rich inequalities were observed, with concentration indices of 0.17 overall, 0.18 at baseline, and 0.15 at endline. Richer households adhered to recommended handwashing practices. Host community status, having young children, seeking care at public facilities, and the availability of handwashing facilities increased inequality. Wealth reduced inequality by 14.2% in the overall sample. Persistent socio-economic disparities in handwashing behaviour highlight the need for interventions that strengthen household economic capacity and access to improved water and sanitation. Prioritising income-generation initiatives, improved water access, and affordable hygiene facilities, alongside inclusive hygiene promotion, can help reduce inequities.