How and why do we study research methods? The TYPE-ME typology of methods research

Background: Methods research aims to develop, evaluate, refine, or provide guidance on research methods, support their implementation or de-implementation, or synthesize existing methods research. Many types of methods research appear in health research journals, but their labels, definitions, and boundaries remain unclear. This complicates planning, reporting, indexing, and teaching, and limits the visibility of the field. We aimed to develop, refine and pilot-test a typology for recognising, describing, and classifying methods research. Methods: An international panel of 11 methodologists developed the typology through written feedback, structured group discussions, and iterative revision. In two testing rounds, panel members independently applied the typology to 52 methods research articles from 26 journals, generating 494 article assessments. We used the results to refine definitions and labels, add boundary notes, and document remaining disagreements. Results: TYPE-ME defines methods research and organizes it along two cross-cutting dimensions: approach (“how?”, 15 types) and objective (“why?”, 14 types). Testing clarified difficult boundaries and led to a condensed version that distinguishes 10 types for quick orientation: theory-based methods research; simulation studies; methods research based on real data; methodological randomized studies; surveys, interviews, or focus groups; consensus studies; studies of applied methods; syntheses of methods research; guidance for applying, reporting, or assessing methods; and methodological implementation research. Detailed type descriptions, boundary notes, and examples appear in an accompanying document and at www.methods-research.org. Conclusions: TYPE-ME offers a common reference for recognising, describing, and classifying methods research, and can support its planning, reporting, indexing, and teaching. As a living typology, it will evolve through application, user feedback, and further testing.