Comparative method, also known as grounded theory, is a systematic qualitative research methodology in the social sciences emphasizing generation of theory from data in the process of conducting research. It was developed by two sociologists, Barney Glaser and Anselm Strauss.
The structutre of comparative method is completely opposite to a scientific method of a research.
First of all, all the various data is collected. After that some key points are taken from the data and they are marked with a series of codes. The codes are grouped into similar concepts, in order to make them more workable. From these concepts categories are formed, which are the basis for the creation of a theory.