The “core category” of grounded theory: Making constant comparisons

Approximately 40 years ago, Barney Glaser and Anselm Strauss and their joint research approach, the constant comparative method of grounded theory, were at the forefront of what can be called a qualitative revolution. The publication of their book, The discovery of grounded theory (1967), was a breakthrough because of the systematic procedures for qualitative research that were presented. Prior to this publication, qualitative research methodology was traditionally most often taught orally. Through their book, Glaser and Strauss defended the method of qualitative research and countered the prevailing opinion that quantitative research provided the one and only approach to scientific inquiry. They argued that qualitative research is a field of inquiry in its own right, not merely to be used for pre-studies to “real” statistically based studies. The grounded theory method fits in with life world research, because the emphasis is on individuals as unique living wholes and the researcher focuses on the world as it is experienced by the individual. The researcher does not formulate any hypothesis in advance and tries to approach the research area with as few preconceptions as possible. Preconceptions, taken-for-granted assumptions, and interpretations must be handled by reflexive strategies in line with what Dahlberg () has labelled “bridling”. Grounded theory offers the researcher a set of guidelines for building conceptual frameworks that specify the relationships among categories. The guidelines should be used as flexible tools rather than being seen as rigid rules. Grounded theory is a broad method with distinct procedures that work in practice and that are suitable to pragmatic researchers. The “core category” in grounded theory is, as I see it, the constant comparative method. The grounded theory method has been modified by the era within which it exists and by new ideas encountered in the world of inquiry (Annells, ). Varying views of what reality is and how it can be known affect the modes of the grounded theory method.