To assess the prevalence and magnitude of undisclosed financial conflicts of interest (COIs) among physician-authors in high-impact US-based psychiatry journals.

Cross-sectional study comparing the author self-reported disclosures to the journal(s) with payments mandatorily reported in the Open Payments database.

We examined original research articles published between 1 January 2020 and 31 December 2022 in two prominent US-based psychiatry journals: the American Journal of Psychiatry (AJP) and Journal of the American Medical Association Psychiatry (JAMA-PSY). Of 2872 publications screened, 74 articles authored by 27 eligible US-based physician-authors met the inclusion criteria.

Total payments received by authors within the 3 years prior to publication and the proportion of undisclosed payments. Additional analyses assessed payment types (research vs general), author demographics and study characteristics associated with undisclosed COIs.

US$4.54 million was paid to authors in the two journals, of which US$645 135 (14.2%) were undisclosed. AJP authors received US$205 943 (7.5% of total payments) in undisclosed payments, while JAMA-PSY authors received US$439 192 (24.8%). Research payments constituted 82.3% of all undisclosed payments. Total undisclosed payments among the top 10 highest-earning authors accounted for 84.8% (AJP) and 99.6% (JAMA-PSY) of all undisclosed payments to journals. Nearly all undisclosed payments, 96.2%, were made to authors conducting randomised controlled trials.

Substantial undisclosed financial COIs were identified among the top 10 earners in high-impact psychiatry journals. These findings highlight potential risks to research transparency and integrity. Further research is needed to evaluate the effectiveness of disclosure policies and develop mechanisms to mitigate COIs in psychiatric research.