Background: Coronavirus disease 2019 (COVID-19) is a rapidly spreading disease that has caused an extensive burden to the world. Consequently, a large number of clinical trials have examined the efficacy of traditional Chinese medicine (TCM) for treating and preventing COVID-19, with coinciding proliferation of reviews summarizing these studies.
Objective: This study aimed to evaluate the methodological quality and evidence quality of systematic reviews and meta-analyses on the efficacy of TCM.
Search strategy: Seven electronic databases, including PubMed, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Chongqing VIP, Wanfang Data and SinoMed, were searched for systematic reviews and meta-analyses in October 2021. Search terms such as “Chinese medicine,” “Lianhua Qingwen” and “COVID-19” were used.
Inclusion criteria: Systematic reviews and meta-analyses of randomized controlled trials that evaluated the efficacy of TCM treatment of COVID-19 were included.
Data extraction and analysis: A Measurement Tool to Assess Systematic Reviews Version 2.0 (AMSTAR 2) was used to evaluate the methodological quality. The quality of evidence was graded using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Data extraction and analysis were performed by two reviewers independently.
Results: There were 17 meta-analyses included in our overview. The intervention group was defined as TCM combined with Western medicine, while the control group was Western medicine alone. The methodological quality of all the included studies was moderate to poor. A total of 89 outcome indicators were evaluated, of which, 8 were rated as moderate quality, 39 as low quality, and 41 as very low quality. Only one outcome measure was graded as being of high quality. The moderate quality of evidence indicated that, for the treatment of COVID-19, the clinical efficacy of TCM in combination with Western medicine was better, in terms of lung recovery, rate of conversion to severe/critical cases, symptom scores, duration of symptoms, mortality, and length of hospital stay.
Conclusion: Evidence from the included studies shows that, compared with conventional Western medical therapy alone, the addition of TCM to COVID-19 treatment may improve clinical outcomes. Overall, the quality of evidence of TCM for COVID-19 was moderate to poor. Meta-analyses of the use of TCM in the treatment of COVID-19 can be used for clinical decision making by accounting for the experiences of clinical experts, medical policies, and other factors.