Configurational comparative methods

Configurational comparative methods (CCMs) systematically compare cases (for example, individuals or organizations) to identify combinations of conditions (for example, implementation strategies and contextual factors) that may make a difference for an outcome (for example, implementation). CCMs use the regularity theory of causation and principles of Boolean algebra to identify insufficient but necessary parts of a configuration of conditions which is itself unnecessary but sufficient for the outcome. Thus, CCMs are particularly useful for identifying causal complexity whereby multiple conditions are needed for the outcome to occur. Central to CCMs is the notion of equifinality, that is, more than one set of conditions can lead to the same outcome. CCMs are fundamentally different from inferential statistical methods in several important ways; these differences contribute to the usefulness of CCMs for research using a range of sample sizes and quantitative and qualitative data sources. CCMs have the potential to identify key conditions for implementation.