Automated Surveillance of Primary Outcome Reporting in Clinical Trials: Development and Validation of a Scalable Screening Pipeline

Version 2.1 (September 2026). Accepted manuscript of an article accepted for publication in Clinical Trials (version of record: https://doi.org/10.1177/17407745261491903), incorporating the author's corrections made at the proof stage.

Changes from version 2.0: the number of studies included in the systematic review by Jones et al. (2015) is corrected from 16 to 27; the range of discrepancy rates attributed to prior studies is corrected to 15–62% to match the cited sources; an unsupported citation (Bourgeois et al., 2010) is removed; and four reference entries (FDAAA statute, ClinicalTrials.gov PRS user's guide, AllTrials campaign, ICH E8 guideline) are completed or updated with current URLs. Results, figures, tables and supplementary material are unchanged.

The study describes an automated pipeline that screens primary-outcome reporting across 46,365 completed interventional trials with posted results on ClinicalTrials.gov (2015–2025), comparing registered primary outcomes with published results and validating against manual review of 123 trial-publication pairs. Flags denote prompts for review, not confirmed discrepancies. Code and data are available at https://github.com/hayden-farquhar/Outcome-Switching-Study