Quality & Quantity 36: 391–409, 2002.
© 2002 Kluwer Academic Publishers. Printed in the Netherlands.
A Purposeful Approach to the Constant
Comparative Method in the Analysis of Qualitative
Utrecht University, Faculty of Social Sciences, Department of Methodology & Statistics, PO Box
80140, 3508 TC Utrecht, The Netherlands (E-mail: email@example.com)
Abstract. 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.
Key words: qualitative research, constant comparative method, grounded theory, qualitative analysis,
The constant comparative method (CCM) together with theoretical sampling con-
stitute the core of qualitative analysis in the grounded theory approach developed
by Glaser and Strauss (Glaser and Strauss, 1967; Strauss, 1987; Glaser, 1992).
Comparison is also the dominant principle of the analysis process in other tradi-
tions of qualitative research. All kinds of aids, such as memo writing, close reading
and rereading, coding, displays, data matrices and diagrams support the principle
of comparison. Many academic works have offered interpretations, explanations
and illustrations of grounded theory, as well as providing relevant techniques, pro-
cedures and rules of thumb (Strauss and Corbin, 1998; Wester, 1995; Denzin and
H. R. Boeije, Ph.D. works as an assistant professor in the Department of Methodology and
Statistics of the Faculty of Social Sciences at the University of Utrecht. She specializes in research
and education in the ﬁeld of qualitative methods.