Impact Evaluation of Service Delivery Programs: Methods and Concepts for Impact Assessments in Basic Education, Health, Water and Sanitation

"This paper is an introduction and, to some extent, a practical guide for researchers and practitioners interested in impact evaluation in education, health, water and sanitation. However,since the methods and concepts dealt with in this paper do not only apply to these sectors, the paper should be of more general interest.The outline of the paper is as follows. In section 2, we discuss the question: What type of intervention/projects should one evaluate? Section 3 discusses the issue of structural and reduced form relationships. The main section, section 4, discusses the evaluation problem, or the selection bias problem, and reviews both randomized and non-randomized methods that have been developed to deal with this bias. Section 5 discusses inference issues, including problems associated with measurement errors and grouped data. Section 6 discusses data issues and power calculations and section 7, finally, concludes the paper."