Water Treatment and Child Mortality: A Meta-analysis and Cost-effectiveness Analysis

Randomized controlled trials (RCTs) of water treatment are typically powered to detect effects on caregiver-reported diarrhea but not child mortality, as detecting mortality effects requires prohibitively large sample sizes. As a result, water treatment is often not included in lists of cost-effective, evidence-backed child survival interventions which are recommended for prioritization in health funding decisions, and health funds are typically not used to cover the cost of water treatment at scale. To increase statistical power, we conducted a meta-analysis that combined available RCT evidence on child mortality with new evidence on mortality obtained from authors of studies reporting only diarrhea outcomes.

We find that water treatment reduced the odds of child mortality (death before age five) by about 30%. This suggests that water treatment is a highly cost-effective way of saving lives. It costs roughly $3,000 to save a child’s life through water treatment, or around $40 per healthy life year (HLY). This analysis suggests that water treatment should be a priority for policymakers aiming to improve child health.