Mixed methods (MM) evaluations seek to integrate social science disciplines with predominantly quantitative (QUANT) and predominantly qualitative (QUAL) approaches to theory, data collection, data analysis and interpretation. The purpose is to strengthen the reliability of data, validity of the findings and recommendations, and to broaden and deepen our understanding of the processes through which program outcomes and impacts are achieved, and how these are affected by the context within which the program is implemented. While mixed methods are now widely used in program evaluation, and evaluation RFPs frequently require their use, many evaluators do not utilize the full potential of the MM approach.
This guidance note explains the essential elements of the MM approach and how it can be used in an impact evaluation (IE), while highlighting potential applications and benefits for NGOs. Part I addresses the question, “Why mixed methods?” We discuss what an MM impact evaluation design is, what distinguishes it from a QUANT or QUAL impact evaluation design and why the approach is helpful for understanding development evaluations and the complexities of the real world within which they are implemented (section 1.1). The increasing popularity of MM comes from the recognition of the limitations of an exclusive reliance on either QUANT and QUAL methods (section 1.2), and the potential benefits that can be achieved when both approaches are appropriately combined (section 1.3). While MM can be used as part of a large and well-funded impact evaluation, the methods have the flexibility to be equally useful for the many NGOs that require credible evaluations of their programs, but whose resources and expertise for con cting impact evaluations are limited.