The joint effects of efficacy and compliance: A study of household water treatment effectiveness against childhood diarrhea

► Household water treatment (HWT) can prevent diarrhea in developing countries. ► Increasing HWT log10 removals has diminishing returns if compliance is ≤ 99%. ► Higher HWT log10 removals prevent more diarrhea if water is highly contaminated. ► HWT compliance in communities is poorly characterized & must be carefully measured.