Transparency of clinical practice guideline funding: A cross-sectional analysis of the German AWMF registry

Background: While reporting of individual conflicts of interest is formalized, it is currently unclear to what extent the funding is reported in clinical practice guidelines (CPGs). The aim of this study therefore was to explore the quality of reporting on funding in German CPGs. Methods: : We searched for available CPGs in the registry of the Association of the Scientific Medical Societies in Germany in July 2020. Information on guideline funding was categorized by two reviewers independently and discrepancies were clarified by discussion with a third reviewer. The editorial independence of the funding body was assessed with the German Instrument for Methodological Guideline Appraisal (DELBI). Results: : We analyzed 762 CPGs, 60.6% (462) of these provided interpretable information. Transparency increased with the methodological requirements of the respective guideline tier but only 3.5% (27) of CPGs achieved the highest DELBI score. Funding sources and expenses were dependent of the CPG tier. Conclusion: Funding practices are not communicated transparently in German CPGs. There is no definite picture of exact funding sources, expenses and volumes throughout all guideline tiers. This study aims to foster public discussion and increased transparency of guideline funding to improve the development of and trust in CPGs.