A Reporting Guideline for Observational Studies in Metabolomic Epidemiology: Explanation and Elaboration of the Strobe-MetEpi Checklist.

Metabolomic epidemiology has expanded rapidly, but publications often lack sufficient detail for readers to assess study design, analytical methods, sources of bias, and the robustness and reproducibility of findings. Existing reporting recommendations in epidemiology and metabolomics do not fully address the specific challenges that arise when these fields are combined. To improve the completeness and transparency of reporting, we developed the Strengthening the Reporting of Metabolomic Epidemiology (STROBE-MetEpi) statement, an extension of the original STROBE guidance for observational research. The STROBE-MetEpi checklist includes 31 items and subitems covering the Title, Abstract, Introduction, Methods, Results, Discussion, and Other Information sections of metabolomic epidemiology studies. This explanation and elaboration document is intended to complement the STROBE-MetEpi statement by explaining the rationale for each checklist item and providing published examples of transparent reporting. It applies to studies using metabolomic profiling to explore human health, but not to randomized trials, methodological studies, reviews, or multi-omics studies. As with previous STROBE explanation and elaboration documents, its purpose is to improve how studies are reported, not to prescribe how they should be conducted. The STROBE-MetEpi statement and this accompanying document should support authors, reviewers, editors, and readers in improving the reporting, appraisal, interpretation, and reproducibility of metabolomic epidemiology research.