Application of the Templates TIDieR and CERT Reveal Incomplete Reporting and Poor Replicability of Exercise Interventions for Type 2 Diabetes Mellitus

Background: Exercise is strongly recommended for the management of type 2 diabetes mellitus (T2DM). However, incomplete intervention reporting in clinical trials limits the replication of exercise protocols. As previously demonstrated by us for exercise and hypertension, the reporting quality might also be insufficient in studies with respect to T2DM and exercise. Objective: The aim of the study was to assess the completeness of exercise intervention reporting in randomized controlled trials (RCTs) for T2DM. Methods: Two independent reviewers applied the Consensus on Exercise Reporting Template (CERT) and the template for intervention description and replication (TIDieR) to 23 exercise trials obtained from the most recent and frequently cited meta-analysis in current guidelines. The completeness of reporting was evaluated, focusing on the F.I.T.T. components (frequency, intensity, time, type). Interrater agreement and associations with publication year and journal impact factor were examined. Results: Mean CERT score was 11/19 (range 5-17), and 8/12 (range 4-12) for TIDieR. F.I.T.T. components were almost completely described, whereas overall completeness of exercise reporting was 60% and 68% (CERT and TIDieR). Replication of each exercise of the respective program was not possible in 52% of interventions. The majority of items had shown excellent agreement. No associations with publication year or impact factor were found. Conclusion: Exercise interventions were not found to be sufficiently reported in RCTs that currently guide clinical practice in T2DM. Replication in further studies or clinical practice is limited due to poor exercise description. We suggest the use of more specific CERT for reporting results of exercise interventions. Further refinement for internal diseases is needed to better describe exercise interventions.