Challenges in Using Mix Methods in Evaluation (English version)

This article explores the debates between quantitative and qualitative methods in the evaluation process, analyzes the challenges about methodological mix in terms of credibility and validity of data and tools, and the evaluation findings. Beyond the epistemological contradictions, it seems that, in terms of usefulness, the mixing of methods is a practical solution, along with hybrids theories, able to provide information to improve the sufficiency of the program. Mixing methods is also a way to reduce conflict between positivism and constructivism and an opportunity for increasing flexibility that the evaluator has in choosing the most appropriate methods for obtaininginformation in the assessment process.mix methods; credibility; internal validity; external validity; program evaluation.