Targeted surveys of participants are increasingly popular in research on political activism. While this strategy solves problems of national surveys by effectively reaching rare types of activists, they also suffer a major drawback: since they only include participants and no “zeros”, i.e. non-participants, they are ill suited to test the determinants of activism. We propose “case-control designs”, widely used in epidemiology, to expand targeted surveys to a more powerful design by supplementing the cases with „zeros“, i.e. eligible controls that allow us to test causal effects. In this regard, the case-control design can smoothly upgrade more qualitatively oriented studies and connect them to quantitative approaches, taking advantage of the strength of both. Using the example of protest participation at a recent anti-austerity demonstration, we illustrate the necessary steps of our appraoch: a) the definition and sampling of participants, b) the selection of zeros and c) the analysis of case-control data.
