Patient-Important Outcomes Reported as Primary Outcomes in Clinical Studies of Treatments for COVID-19: A Meta-Epidemiological Study.

Publication date: Jun 17, 2026

The reporting of patient-important outcomes (PIOs) in randomized controlled trials (RCTs) for COVID-19 varies widely, limiting their application in clinical decision-making. We evaluated how often PIOs were reported as primary outcomes in RCTs of COVID-19 treatments and identified trial characteristics associated with their reporting. This meta-epidemiological study analyzed primary outcome data from 102 RCTs evaluating COVID-19 treatments. Mortality outcomes were more frequently reported in trials with 15-28-day follow-up than in trials with ≤ 14-day follow-up (OR: 3. 53, 95% CI: 1. 10-11. 38), and less frequently in trials enrolling participants with moderate-severity COVID-19 compared with trials not enrolling such participants (OR: 0. 22, 95% CI: 0. 07-0. 64). Morbidity outcomes were less frequently reported in trials enrolling severe-COVID-19 participants compared with trials not enrolling them (OR: 0. 19, 95% CI: 0. 05-0. 78), and more frequently reported in trials conducted in Europe (OR: 12. 78, 95% CI: 1. 01-161. 76), Asia (OR: 11. 03, 95% CI: 1. 50-81. 03) and the Americas (OR: 8. 92, 95% CI: 1. 08-73. 89), each compared with multi-continental trials. Trials with more than 200 participants were also more likely to report morbidity outcomes than trials with ≤ 50 participants (OR: 11. 43, 95% CI: 1. 37-95. 55). Quality of life and functional status outcomes were not associated with any of the predictors examined. Reporting of PIOs as primary outcomes in COVID-19 RCTs is inconsistent and influenced by region, disease severity, and sample size. Quality of life and functional recovery remain overlooked. The implementation of Core Outcome Sets (COS) is required to ensure that PIOs are routinely and consistently incorporated into trial designs.

Semantics

Original Article