Globally around 1.2 billion people live on less than $1 a day. The erosive impact of poverty on their health and the link between ill health and poverty is well known.1 But most interventions aimed at alleviating poverty and improving health in poor countries help the better off more than the most disadvantaged.2 Such inequity of impact is often conveniently masked by expressing outcomes of evaluations as population averages, a flaw inherent even in the three health related millennium development goals. Now a report from the World Bank looks at the evidence and suggests how to reach the poor more effectively.3

The data in the report, from 78 programmes on health, nutrition, and population conducted in 56 …