Objective The objective of this study was to determine the proportion of clinical trials conducted in Canada that adhered to the World Health Organization’s registration and reporting best practices. The specific contributing factors that impaired adherence to those best practices were highlighted.

Design All registered clinical trials on ClinicalTrials.gov conducted in Canada as of 2009 and completed by 2019 were identified. A cross-sectional analysis of those trials measured prospective registration (as opposed to retrospective registration), subsequent result reporting in the registry at any point, and subsequent publication of study findings at any point. Unregistered and/or incomplete clinical trials were excluded. This means that the results likely underestimate the true prevalence of nonreporting of trials conducted in Canada. The lead sponsor, phase of study, countries involved, total patient enrollment, number of arms, type of masking, type of allocation, year of completion, and patient demographics were examined as potential effect modifiers to these best practices.

Results A total of 6720 trials met the inclusion criteria. From 2009 to 2019, 59% (n = 3967) of clinical trials were registered prospectively and 39% (n = 2642) reported their results in the registry. Of the trials registered between 2009 and 2014, 55% (n = 1482) were subsequently published in an academic journal. Over time, the annual rate of compliance with study registration and subsequent publication of findings improved (increased). However, there was a downward trend over time in results being reported in the registry. Of the 3763 trials conducted exclusively in Canada, 3% (n = 123) met all 3 criteria of prospective registration, reporting in the registry, and publishing findings. In contrast, of the remaining 2957 trials with both Canadian and international sites, 41% (n = 1238) had an overall compliance to these 3 criteria.

Conclusions Canadian clinical trials substantially lacked adherence to study registration and reporting best practices. Knowledge of this widespread noncompliance should motivate stakeholders in the Canadian clinical trial ecosystem to address and continue to monitor this problem. The data presented provide a baseline against which to compare any improvement in the registration and reporting of clinical trials in Canada.

Conflict of Interest Disclosures David Moher is an associate director and member of the Peer Review Congress advisory board and An-Wen Chan is a member of the Peer Review Congress advisory board but neither were not involved in the review or decision for this abstract. No other conflicts of interest to declare.

Funding/Support This study was funded by the University of Ottawa Summer Studentship Program. This program provides a stipend for a University of Ottawa medical student’s summer research project.

Role of the Funder/Sponsor The funding organization had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the abstract; and decision to submit the abstract for presentation.