Challenges of consolidating evidence collected during a pandemic and lessons for the future

To illustrate the challenges encountered when gathering rapidly synthesized evidence in response to the coronavirus disease 2019 (COVID-19) pandemic.

In this article, we describe the challenges encountered when we performed a systematic literature review (SLR) of randomized controlled trials (RCTs) on the efficacy and safety of treatments for severe COVID-19. The methods of the SLR are described in full, to show the context of our objectives. Then we use the results of the SLR to demonstrate the problems of producing synthesized evidence in this setting.

Various challenges were identified during this SLR. These were primarily a result of heterogeneity in the study methodology of eligible studies. Definitions of the patient populations and outcome measurements were highly variable and the majority of studies demonstrated a high risk of bias, preventing quantitative synthesis of the collated evidence.

Consolidating evidence from RCTs evaluating COVID-19 interventions was problematic. Guidance is needed for scenarios with high rapid output in primary research.