Prediction model protocols indicate better adherence to recommended guidelines for study conduct and reporting.

INTRODUCTION: Protocols are invaluable documents for any research study and especially prediction model studies. However, the mere existence of a protocol is insufficient if key details are omitted. We reviewed the reporting, content and details of the proposed design and methods reported in published protocols for prediction model research. METHODS: We searched MEDLINE, Embase and Web of Science Core Collection for protocols for studies developing or validating a diagnostic or prognostic model using any modelling approach in any clinical area. We screened protocols published between 1 Jan 2022 to 30 June 2022. We used the abstract, introduction, methods and discussion sections of The Transparent Reporting of a multivariable prediction model of Individual Prognosis Or Diagnosis (TRIPOD) statement to inform data extraction. RESULTS: We identified 30 protocols, of which 28 were describing plans for model development and 6 for model validation. All protocols were open access including a preprint. 15 protocols reported prospectively collecting data. 21 protocols planned to use clustered data, of which one-third planned methods to account for it. Planned sample size was reported for 93% development and 67% validation analyses. 16 protocols reported details of study registration, but all protocols reported a statement on ethics approval. Plans for data sharing were reported in 13 protocols. CONCLUSION: Protocols for prediction model studies are uncommon and few are made publicly available. Those that are available were reasonably well reported and often described their methods following current prediction model research recommendations, likely leading to better reporting and methods in the actual study.