The impact of improved water and sanitation on water-related diseases: a propensity scores matching analysis from Palghar District, Maharashtra, India

Abstract

Inadequate water, sanitation, and hygiene (WASH) are responsible for a significant portion of the global disease burden. However, establishing the causal effect of improved WASH is challenging due to confounding socioeconomic factors. This study employs propensity score matching (PSM) to estimate the causal effect of improved water and sanitation on water-related diseases in Palghar District, India. Using cross-sectional household survey data, households with improved WASH were matched with statistically similar households without improved WASH. The average treatment effect on the treated (ATT) was estimated for diarrhoea, jaundice, malaria, skin disease, typhoid, and dengue. The analysis reveals a statistically significant reduction in jaundice prevalence (ATT: -0.21, p<0.10) attributable to improved WASH. Effects on diarrhoea, typhoid, and skin disease showed protective trends but were not significant. A counterintuitive finding was a significant increase in malaria risk (ATT: 0.38, p<0.05), potentially linked to water storage practices. The protective effect of improved WASH is not uniform. While critical for faecal-oral diseases like jaundice, its impact is mediated by behavioural and contextual factors. Policy must integrate behavioural change communication, targeted vector control, and equity-oriented interventions.