ABSTRACT
During evaluation of the integrity of 172 clinical trial publications, we identified 138 unique trial registration documents linked to 157 publications. Eighty-eight (64%) registrations were retrospective. Discrepancies in key trial characteristics – ethics oversight, study timeline, study location, participant number and sample size – between 68 registration documents and their linked publications were reported to journals, publishers and a national regulatory body. Subsequently, revisions to 119/138 registration documents were lodged at the registry website, a median (IQR) of 44 (32–56) months after initial registration. Revisions were made to 56 of the 68 registration documents included in the report: there was a median of 8 (IQR 6–9) changes per document. 79–93% of revised documents contained ≥1 alteration to the primary outcome(s), the secondary outcome(s), and the participant inclusion/exclusion criteria. Changes in each of study location, study timeline, participant age, sample size, and randomization method were made in ≥33% of revised documents. Eight months after journals, publishers and the regulatory body were apprised of the revisions, none of the affected publications has been corrected with an , expression of concern, or retraction. These results call into question whether regulators and publishers regard trial registration documents as helpful in ensuring publication integrity.
Authors’ contributions
Andrew Grey-study design, data acquisition, data interpretation, data analysis, drafting of manuscript; Richard Portch – data acquisition, data interpretation; Alan Gaby – data acquisition, data interpretation; Hamish Grey – data acquisition; Mark Bolland – study design, data interpretation. All authors revised the manuscript and approved the submitted version.
Availability of data
Data are available from the corresponding author upon reasonable request.
Code availability
Not applicable.
Consent to participate
Not applicable.
Consent for publication
Not applicable.
Disclosure statement
No potential conflict of interest was reported by the authors.
Ethical approval
Not applicable.
Supplementary material
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