In recent years, developing-country governments, donors, and practitioners have sounded increasingly urgent calls for better identification of effective interventions in all sectors (see, for example, Duflo & Kremer, 2003; Maredia, 2009; Savedoff et al., 2006). In particular, the lack of rigorous studies of social sector programs leaves “decision-makers with good intentions and ideas, but little real evidence of how to effectively spend resources to reach worthy goals” (Savedoff et al., 2006, p. 1). In response to this gap, the interest in impact evaluations has increased substantially, in education as well as in other sectors (Banerjee, 2007).
