Implications of WASH Benefits trials for water and sanitation
Authors: Diane Coffey, Dean Spears
Published in: The Lancet Global Health
This paper argues that while the results of the WASH Benefits trials are important for understanding sanitation intervention and similar programmes, they do not imply that child health would not be improved by a large transition from open defecation to latrine use, especially in a densely populated area, and that these results are consistent with existing observational data.
The WASH Benefits trials study assessed the effect on child height-for-age of “household sanitation upgrades from unimproved to improved latrines” in the child’s compound for Bangladesh and Kenya. They found that child height was not increased by upgrading sanitation facilities. An important aspect of these studies was that the adult latrine use was high at baseline: only about 5% of adults in each setting initially defecated in the open.
The current paper analyses data from two Indian DHS. Unlike in the settings of WASH Benefits, in rural India most people defecate in the open. In both Indian surveys, the fraction of households in a child’s neighbourhood that defecate in the open is associated with a large difference in average child height-for-age. The fraction of households that use improved sanitation is not associated with height once open defecation is controlled. Further demographic evidence suggests that the health consequences of open defecation are greater where population density is high; if so, children in rural India are at especially high risk.