Using propensity score matching to evaluate the impact of household water treatment on childhood diarrhea: evidence from water-stressed rural settings

ABSTRACT Childhood mortality due to diarrheal disease remains a significant concern, constituting over one in ten child deaths in eastern Ethiopia. This study aims to estimate the effects of adopting household water treatment (HWT) methods on the prevalence of under-five children's diarrhea in the Harari region, eastern Ethiopia. Three commonly applied methods (i.e., chlorination, boiling, and filtration) were considered using propensity score matching. The study shows that 31.3% (95% CI: 22.1–40.5%) of households adopt at least one or a combination of HWT methods. The average treatment effect on the treated values based on all matching algorithms shows that households adopting HWT methods have a 10 percentage point lower prevalence of diarrhea than non-adopters, with a range between 8.6 and 11.6 percentage points. Moreover, the impact of each method reveals that households adopting chlorination have shown a statistically significant effect in reducing childhood diarrhea by 15.3 percentage points. However, the effect is not significant for boiling and filtration. This suggests the need to empower and train resource-limited communities in the effective use of boiling and filtration methods. The study highlights the policy implication that promoting the adoption of HWT methods, particularly emphasizing chlorination, can alleviate the burden of childhood diarrhea morbidity.