Funder and authors' financial conflicts of interest information in trial publications: adequacy of reporting and obtaining missing information

OBJECTIVES: To assess the adequacy of reporting of funder and authors' financial conflicts of interest information in randomized trial publications of drugs or devices, and to assess to which degree the missing information can be obtained from other sources.

STUDY DESIGN AND SETTING: We took a random sample of 200 randomized trial publications indexed in MEDLINE in May 2022. Two authors independently assessed the adequacy of funder and authors' conflicts of interest information. We considered funder information adequate when name of funder(s), type(s) of support, and funder's involvement were reported. Similarly, we considered authors' financial conflicts of interest information adequate when name of organization(s), type of relationship(s), and the involvement of author(s) with financial conflicts of interest were reported. We attempted to obtain missing information through multiple approaches (eg, searching websites, trial registries, and public disclosure databases) and recorded the time taken.

RESULTS: We found that information on funder was adequately reported in 67 (34%) trial publications, partly adequate in 110 (55%), inadequate in 12 (6%), and 11 (6%) had no information available. Often, trial publications did not report the type(s) of support (40%) and the funders' involvement in the trial design, conduct, analysis, and reporting (58%). After obtaining missing information, the proportion of trial publications with adequate funder information increased by 32% (we obtained information on all domains for 64 of 133 trial publications) by spending a median time of 13 minutes per trial. Information on authors' financial conflicts of interest was adequately reported in 180 (90%) trial publications, and we obtained the missing information for four trials (20%) by spending a median time of 28 minutes per trial.

CONCLUSION: In contemporary trial publications, funder information was rarely adequately reported, whereas authors' financial conflicts of interest information was adequately reported in almost all trial publications. Our approaches for obtaining missing information improved the adequacy of funder and conflicts of interest information. Our approaches were particularly effective in obtaining funder information, whereas efforts to obtain conflicts of interest information were less successful and more time-consuming. Our findings provide context for systematic review authors when deciding if and how to search for missing funder and conflicts of interest information while balancing the need for obtaining information with the time spent searching.