Bolstering Demand for Sanitation in Bangladesh

Project Summary
One billion people, or about 15% of the world’s population, currently practice open defecation, and another 1.5 billion do not have access to an improved sanitation facility (WHO/UNICEF 2014).  The prevalence of open defecation and unimproved sanitation facilities imposes a high public health cost, even on households that do not engage in open defecation, since they are still exposed to fecal matter contaminants in their food and water supply.  Researchers suggest that inadequate sanitation contributes to high rates of diarrheal disease causing 20% of diarrhea-related deaths – approximately 280,000 in 2012 alone (Prüss-Üstün et al. 2014).

In this project, we partnered with VERC and WaterAid Bangladesh to design, implement and test a multitude of marketing treatments intended to increase the purchase, adoption and use of hygienic latrines.  The result was a large scale randomized controlled trial covering over 18,000 households in about 380 communities designed to understand the importance of financial and information constraints, collective action problems and the effectiveness of different marketing strategies that counter these barriers to adoption.

During this RCT we tested the efficacy of three main interventions intended to increase hygienic latrine ownership.  The first intervention, the Latrine Promotion Program (LPP), was designed to address any lack of knowledge about he importance of sanitation and to encourage community coordination to address collective action problems.  We based the LPP intervention on the Community-Led Total Sanitation (CLTS) model, but modified it to place a particular focus on hygienic lattrines.  The second intervention, Latrine Suppy Agents (LSA), was designed to address difficulties faced by households who are willing and financially able to purchse a latrine, but lack the technical knowledge to make an information decision.  We trained the  LSA to provide information on where to purchase latrine parts, how to assess their quality and how to install and maintain a latrine.  The third intervention addressed financial barriers to latrine adoption through subsidies.  Lottery winners received vouchers redeemable for approximately 50% of the price of to purchase and install a hygienic latrine.  We also varied the precentage of lottery participants drawn as winners into three intensity groups: low (25% winners), medium (50% winners) and high (75% winners).  This last level of random variation afforded us the ability to examine collective action problems and spillover effects in adoption decisions.

Latrine Adoption and Use Results
Our results suggest that information alone is not the key barrier to latrine adoption.  The LPP and LSA treatments did not increase adoption relative to the control group.  However, we did find that the subsidy treatment had a large and significant impact on latrine adoption.  Even households that lost the subsidy lottery but lived in a village assigned to the subsidy treament were more likely to own a hygienic latrine at follow-up.  We also find that a household’s propensity to continue open defecation is lower if more of their their neighbors got lucky and received toilet vouchers. These results show that households base their latrine purchasing and use decisions in part on the contemporaneous decisions of those around them, even controlling for the price they personally face for a latrine.

The presence of interlinked decision-making has specific implications for the design of effective marketing and latrine promotion strategies. Sanitation interventions will be more cost-effective if they can identify the relevant externality network, and target that group jointly rather than each household individually.  Asking community members to make a joint investment commitment is a good idea, but our results suggest that this should be accompanied with subsidies targeted to the poorest members of the community.  Future programs could further attempt to harness the interplay between subsidies and interlinked decision-making by combining financial incentives with a forum for community cooperation.

The Political Economy of Large Scale Interventions
In addition to the analysis of adoption and use of latrine, we also studied the political economy responses to this large scale intervention.  The plausible argument that aid undermines political accountability by making it difficult for voters to distinguish between good and bad leaders has gained traction in many policy debates.  In theory, large scale interventions have the potential to change the perception of politicians if the constituents attribute credit for non-government programs to a politician.

We take advantage of the scale of our intervention to test if political accountability is easily undermined by development aid.  We find that constituents update positively about their leaders after the arrival of an externally financed development program only if the source of the program is uncertain.  However, simply informing beneficiaries about who is responsible for the program eliminates the excess credit that leaders receive from aid programs. These results suggest that while politicians may attempt to take credit for development programs, it is not easy for them to do.

Research Partners:
Raymond Guiteras (University of Maryland), Jim Levinsohn (Yale University), VERC Bangladesh, WaterAid Bangladesh

Research Papers
R. Guiteras, J. Levinsohn, A.M. Mobarak, “Encouraging Sanitation Investment in the Developing World: A Cluster-Randomized Controlled Trial” Science (April 2015 – Online) Full-text available from Research Page

Abstract: 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=.90). Subsidies to the majority of the landless poor increased ownership among subsidized households (+22.0 percentage points, p<.001) and their unsubsidized neighbors (+8.5 percentage points, p=.001), which suggests investment decisions are interlinked across neighbors. Subsidies also reduced open defecation by 14 percentage points (p<.001).

A. M. Mobarak and R. Guiteras. “Does Development Aid Undermine Political Accountability? Leader and Constituent Responses to a Large-Scale Intervention” Working Paper

Abstract: We study political economy responses to a large scale intervention in Bangladesh, where four sub-districts consisting of 100 villages (12,000 households) were randomly assigned to control, information or subsidy treatments to encourage investments in improved sanitation. In theory, leaders may endogenously respond to large interventions by changing their allocation of effort, and their constituents’ views about the leader may rationally change as a result. In one intervention where the leaders’ role in program allocation was not clear to constituents, constituents appear to attribute credit to their local leader for a randomly assigned program. However, when subsidy assignment is clearly and transparently random, the lottery winners do not attribute any extra credit to the politician relative to lottery losers. The theory can rationalize these observations if we model leaders’ actions and constituent reactions under imperfect information about leader ability. A third intervention returns to program villages to inform a subset of subsidy recipients that the program was run by NGOs using external funds. This eliminates the excess credit that leaders received from treated households after the first intervention. These results suggest that while politicians may try to take credit for development programs, it is not easy for them do so. Political accountability is not easily undermined by development aid.