Poor sanitation remains a major public health concern linked to several important health outcomes; emerging evidence indicates a link to childhood stunting. In India over half of the population defecates in the open; the prevalence of stunting remains very high. Recently published data on levels of stunting in 112 districts of India provide an opportunity to explore the relationship between levels of open defecation and stunting within this population. We conducted an ecological regression analysis to assess the association between the prevalence of open defecation and stunting after adjustment for potential confounding factors. Data from the 2011 HUNGaMA survey was used for the outcome of interest, stunting; data from the 2011 Indian Census for the same districts was used for the exposure of interest, open defecation. After adjustment for various potential confounding factors – including socio-economic status, maternal education and calorie availability – a 10 percent increase in open defecation was associated with a 0.7 percentage point increase in both stunting and severe stunting. Differences in open defecation can statistically account for 35 to 55 percent of the average difference in stunting between districts identified as low-performing and high-performing in the HUNGaMA data. In addition, using a Monte Carlo simulation, we explored the effect on statistical power of the common practice of dichotomizing continuous height data into binary stunting indicators. Our simulation showed that dichotomization of height sacrifices statistical power, suggesting that our estimate of the association between open defecation and stunting may be a lower bound. Whilst our analysis is ecological and therefore vulnerable to residual confounding, these findings use the most recently collected large-scale data from India to add to a growing body of suggestive evidence for an effect of poor sanitation on human growth. New intervention studies, currently underway, may shed more light on this important issue.

Background: Three large new trials of unprecedented scale and cost, which included novel factorial designs, have found no effect of basic water, sanitation and hygiene (WASH) interventions on childhood stunting, and only mixed effects on childhood diarrhea. Arriving at the inception of the United Nations' Sustainable Development Goals, and the bold new target of safely managed water, sanitation and hygiene for all by 2030, these results warrant the attention of researchers, policy-makers and practitioners. Main body: Here we report the conclusions of an expert meeting convened by the World Health Organization and the Bill and Melinda Gates Foundation to discuss these findings, and present five key consensus messages as a basis for wider discussion and debate in the WASH and nutrition sectors. We judge these trials to have high internal validity, constituting good evidence that these specific interventions had no effect on childhood linear growth, and mixed effects on childhood diarrhea. These results suggest that, in settings such as these, more comprehensive or ambitious WASH interventions may be needed to achieve a major impact on child health. Conclusion: These results are important because such basic interventions are often deployed in low-income rural settings with the expectation of improving child health, although this is rarely the sole justification. Our view is that these three new trials do not show that WASH in general cannot influence child linear growth, but they do demonstrate that these specific interventions had no influence in settings where stunting remains an important public health challenge. We support a call for transformative WASH, in so much as it encapsulates the guiding principle thatin any contexta comprehensive package of WASH interventions is needed that is tailored to address the local exposure landscape and enteric disease burden.

Physical height is an important economic variable reflecting health and human capital. Puzzlingly, however, differences in average height across developing countries are not well explained by differences in wealth. In particular, children in India are shorter, on average, than children in Africa who are poorer, on average, a paradox called "the Asian enigma" which has received much attention from economists. This paper provides the first documentation of a quantitatively important gradient between child height and sanitation that can statistically explain a large fraction of international height differences. This association between sanitation and human capital is robustly stable, even after accounting for other heterogeneity, such as in GDP. I apply three complementary empirical strategies to identify the association between sanitation and child height: country-level regressions across 140 country-years in 65 developing countries; within-country analysis of differences over time within Indian districts; and econometric decomposition of the India-Africa height difference in child-level data. Open defecation, which is exceptionally widespread in India, can account for much or all of the excess stunting in India.

Economic theory and conventional wisdom suggest that time preference can cause or perpetuate poverty. Might poverty also or instead cause impatient or impulsive behavior? This paper reports a randomized lab experiment and a partially randomized field experiment, both in India, and analysis of the American Time Use Survey. In all three studies, poverty is associated with diminished behavioral control. The primary contribution of this empirical paper is to isolate the direction of causality from poverty to behavior. Three similar possible theoretical mechanisms, found in the psychology and behavioral economics literatures, cannot be definitively separated. One supported theoretical explanation is that poverty, by making economic decision-making more difficult, depletes cognitive control.

In this paper, we shed new light on a long-standing puzzle: In India, Muslim children are substantially more likely than Hindu children to survive to their first birthday, even though Indian Muslims have lower wealth, consumption, educational attainment, and access to state services. Contrary to the prior literature, we show that the observed mortality advantage accrues not to Muslim households themselves but rather to their neighbors, who are also likely to be Muslim. Investigating mechanisms, we provide a collage of evidence suggesting externalities due to poor sanitation are a channel linking the religious composition of neighborhoods to infant mortality. In this paper, we address a long-standing puzzle in the development and health literature: In India, Muslim children are substantially more likely than Hindu children to survive to their first birthday, even though Muslims have lower wealth, consumption, and educational attainment, and face worse access to state services such as piped water and health infrastructure, compared to the majority Hindus. 1 By age one, mortality among Muslims is 17% lower than among Hindus, with an additional 1.1 infants per 100 surviving. Bhalotra, Valente and van Soest (2010) named this robust and persistent pattern a "puzzle," showing that individual and household characteristics could not explain it. 2 After replicating the fact that Muslim children have a large survival advantage in India, we show that the mortality difference can be accounted for by two facts. First, compared to the typical Hindu infant, the typical Muslim infant lives in a neighborhood where a larger share of her neighbors are Muslim. Second, both Hindu and Muslim infants are more likely to survive in neighborhoods with high shares of Muslim neighbors. The natural question, then, is: what makes neighborhoods disproportionately inhabited by Muslims better places for the health of (Muslim and Hindu) children? Michael Geruso University of Texas at AustinWe show, consistent with the well-known relative disadvantage of Muslims in India (Sachar et al., 2006 andDeolalikar, 2008), that neighborhoods with high shares of Muslim households are associated with worse characteristics that predict infant health along many observable dimensions-with the important exception of sanitation.Despite relative economic advantage, India's majority Hindu population is 25 percentage points more likely to defecate in the open-that is, in open places such as in fields, behind bushes, or near roads-than the minority Muslim population. This Hindu-Muslim behavioral difference implies that the fraction of a household's neighbors who are Muslim is strongly correlated with the local sanitation environment to which the household is exposed. For example, in nationally representative data, Hindus residing in neighborhoods that are 10% Muslim are exposed to a local open defecation prevalence of 63%, while Hindus residing in neighborhoods that are 90% Muslim are exposed to a local open defecation prevalence of 46%. To better unders...