22 May 2015 vol 348, issue 6237, pages 833-940
Encouraging sanitation investment in the developing world: A cluster-randomized trial
Raymond Guiteras1, James Levinsohn2, Ahmed Mushfiq Mobarak2,*
1Department of Economics, University of Maryland, College Park, MD 20742, USA.
2School of Management, Yale University, New Haven, CT 06520, USA.
Poor sanitation contributes to morbidity and mortality in the developing world, but there is disagreement on what policies can increase sanitation coverage. To measure the effects of alternative policies on investment in hygienic latrines, we assigned 380 communities in rural Bangladesh to different marketing treatments—community motivation and information; subsidies; a supply-side market access intervention; and a control—in a cluster-randomized trial. Community motivation alone did not increase hygienic latrine ownership (+1.6 percentage points, P = 0.43), nor did the supply-side intervention (+0.3 percentage points, P = 0.90). Subsidies to the majority of the landless poor increased ownership among subsidized households (+22.0 percentage points, P < 0.001) and their unsubsidized neighbors (+8.5 percentage points, P = 0.001), which suggests that investment decisions are interlinked across neighbors. Subsidies also reduced open defecation by 14 percentage points (P < 0.001).