Process tracing is a method used to evaluate and develop theories in political science.[1]
The method works by extracting all of the observable implications of a theory, rather than merely the observable implications regarding the dependent variable. Once these observable implications are extracted (particularly with reference to the microfoundations of how a theory's independent variable causes the predicated change in the dependent variable) they are then tested empirically, often through the method of elite interviews but also often through other rigorous forms of data analysis.[2]
It is often used to complement comparative case study methods. By tracing the causal process from the independent variable of interest to the dependent variable, it may be possible to rule out potentially intervening variables in imperfectly matched cases. This can create a stronger basis for attributing causal significance to the remaining independent variables.[3]