How were the Reaching the Poor studies done?

Citation

Wagstaff, A., & Waters, H. (2005). How were the Reaching the Poor studies done? In D. R. Gwatkin, A. Wagstaff, & A. S. Yazbeck (Eds.), Reaching the Poor with Health, Nutrition, and Population Services: What Works, What Doesn't, and Why (pp. 27-46). Washington, DC: The World Bank.

Abstract