Research methods identified in the primary studies on Software Product Management

This file contains a classification table of the research methods identified across the 38 primary studies analyzed in a systematic literature review on Software Product Management (SPM). The table categorizes the studies into guidelines, empirical studies, techniques, tools, and datasets, according to the methodological approach reported in each study. For each category, the table includes a technical description, the number of associated studies, and the identifiers of the primary studies assigned to that category. This supplementary material is provided to support the methodological transparency and reproducibility of the review process.