Zeitschrift für Evaluation: Issue 2/2025, 24. Volume Qualitative Comparative Analysis as a Method for Evaluation Studies

Qualitative Comparative Analysis (QCA) is an increasingly popular method in evaluation studies. QCA aims at systematic, formalised comparisons of cases on the basis of set theory. It uses Boolean algebra to detect necessary and sufficient conditions for an outcome of interest. The article discusses the advantages and drawbacks of the method in the context of evaluations and explains the core concepts of QCA – both for its Crisp- and Fuzzy-Set variants. Moreover, it presents key steps of the QCA procedure when applied to evaluation studies, including calibration, the search for necessary conditions, the setup of truth tables, and different solution types. Building on this, we briefly elaborate on preconditions under which QCA may be a valuable tool for evaluation research.

Keywords
Qualitative Comparative Analysis (QCA), evaluation, method, necessary condition, sufficient condition, set theory