Outcomes evaluated in controlled clinical trials on the management of COVID-19: A methodological systematic review

It is crucial that randomized controlled trials (RCTs) on the management of coronavirus disease 2019 (COVID-19) evaluate the outcomes that are critical to patients and clinicians, to facilitate relevance, interpretability, and comparability.

This methodological systematic review describes the outcomes evaluated in 415 RCTs on the management of COVID-19, that were registered with ClinicalTrials.gov, by 5/5/2020.

Significant heterogeneity was observed in the selection of outcomes and the instruments used to measure them. Mortality, adverse events and treatment success or failure are only evaluated in 64.4%, 48.4% and 43% of the included studies, respectively, while other outcomes are selected less often. Studies focusing on more severe presentations (hospitalized patients or requiring intensive care) most frequently evaluate mortality and adverse events, while hospital admission and viral detection/load are most frequently assessed in the community setting. Outcome measurement instruments are poorly reported and heterogeneous. In general, simple instruments that can control for important sources of bias are favoured. Follow-up does not exceed one month in 64.3% of these earlier trials, and long-term COVID-19 burden is rarely assessed.

The methodological issues identified could delay the introduction of potentially life-saving treatments in clinical practice. Our findings demonstrate the need for consensus in the design of RCTs.