Evaluating the health impact of urban WASH programmes: an affordable approach for enhancing effectiveness

This paper argues for more widespread evaluation of the health
impacts of WASH interventions: not with the aim of demonstrating
that WASH can improve health (we know it can), but rather with
the aim of assessing the impact of particular interventions. We
suggest that more frequent evaluation could contribute to improved
effectiveness, by encouraging investors and implementers to focus on
impacts rather than outputs (such as number of toilets constructed).
More widespread health impact evaluation would also enable more
objective comparative assessment of the value-for-money of different
types of urban WASH intervention. Further, we argue that health
impact evaluation need not be as costly as is widely thought. We
discuss available methods, and suggest that the most appropriate
approach in urban WASH evaluation contexts will often be the
before-after concurrent control (BAC) design.