Evaluating the Impact on Child Mortality of a Water Supply and Sewerage Expansion in Quito: Is Water Enough?

This paper explores the impact that a water supply and sewerage (W&S) expansion had on child mortality in Quito, Ecuador. Studies have typically estimated the effects of this type of interventions comparing outcome indicators - at the aggregate level - of areas with the facilities and areas that lack them, quite often neglecting systematic differences between treated and nontreated areas. Moreover, at aggregate levels, on the one hand, less comprehensive information may imply greater unobserved and uncontrolled heterogeneity; on the other, heterogeneity within areas may jeopardize identification of impacts. To account for these key observations, the authors used a propensity score matching (PSM) analysis at the individual level. Using indirect methods based on census data they constructed a mortality index at the motherhood level, and calculated five different impact estimators based on the propensity scores.