A purposeful approach to the constant comparative method in the analysis of qualitative interviews

The constant comparative method (CCM) together with theoretical sampling constitute the core of qualitative analysis in the grounded theory approach and in other types of qualitative research. Since the application of the method remains rather unclear, researchers do not know how to 'go about' the CCM in their research practice. This study contributes to a purposeful approach of the CCM in order to systematize the analysis process and to increase the traceability and verification of the analyses. The step by step approach is derived from and illustrated with an empirical study into the experience of multiple sclerosis (MS) by patients and their spousal care providers. In this study five different steps were distinguished on the basis of four criteria: (1) the data involved and the overall analysis activities, (2) the aim, (3) the results and (4) the questions asked. It is concluded that systematization of qualitative analysis results from the researcher using a sound plan for conducting CCM regarding these four aspects.