This paper presents a synthetic review of impact evaluations examining effectiveness of water, sanitation, and hygiene interventions in reducing diarrhoea among children. The evaluations were conducted in 35 low- and middle-income countries during the past three decades. The paper challenges the...

In 2004, a landmark study showed that an inexpensive medication to treat parasitic worms could improve health and school attendance for millions of children in many developing countries. Eleven years later, a headline in the Guardian reported that this treatment, deworming, had been "debunked."...