Targeting health subsidies through a non-price mechanism: A randomized controlled trial in Kenya

Free provision of preventive health products can dramatically increase access in low income countries. A cost concern about free provision is that some recipients may not use the product, wasting resources. Yet charging a price to screen out non-users may screen out poor people who need and would use the product. We report on a randomized controlled trial of a screening mechanism that combines free provision of chlorine solution for water treatment with a small non-monetary cost (voucher redemption). Relative to a non-voucher free distribution program, this mechanism reduces the quantity of chlorine procured by 60 percentage points, but reduces the share of households whose stored water tests positive for chlorine residual by only one percentage point, dramatically improving the tradeoff between over-inclusion and over-exclusion.