Objectives: To systematically evaluate timely reporting of clinical trial results at medical universities and university hospitals in the Nordic countries.

Study Design and Setting: In this cross-sectional study, we included trials (regardless of intervention) registered in the European Union (EU) Clinical Trials Registry and/or ClinicalTrials.gov, completed 2016-2019 and led by a university with medical faculty or university hospital in Denmark, Finland, Iceland, Norway, or Sweden. We identified summary results posted at the trial registries and conducted systematic manual searches for results publications (eg, journal articles, preprints). We present proportions with 95% confidence intervals (CI) and medians with interquartile range (IQR). Protocol: https://osf.io/wua3r.

Results: Among 2112 included clinical trials, 1650 (78.1%, 95% CI 76.3%-79.8%) reported any results during our follow-up; 1097 (51.9%, 95% CI 49.8%-54.1%) reported any results within 2 years of the global completion date; and 48 (2.3%, 95% CI 1.7%-3.0%) posted summary results in the registry within 1 year. The median time from global completion date to results reporting was 690 days (IQR 1103). 856/1681 (50.9%) of ClinicalTrials.gov registrations were prospective. Denmark contributed approximately half of all trials. Reporting performance varied widely between institutions.

Conclusion: Missing and delayed results reporting of academically led clinical trials are a pervasive problem in the Nordic countries. We relied on trial registry information, which can be incomplete. Institutions, funders, and policymakers need to support trial teams, ensure regulation adherence, and secure trial reporting before results are permanently lost. (c) 2025 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).