Methodological key points and reporting suggestions for retrospective case series study on using traditional Chinese medicine for treatment of COVID-19

ABSTRACT

Recently a series of case-analysis articles have been published in Chinese Journals for traditional Chinese medicine treatment of coronavirus disease-2019 (COVID-19). Most of them were retrospective case series study. Considering the characteristics and methodological limitations of such kinds of research, authors aimed to introduce reasonable methodological key points and reporting suggestions for uncontrolled retrospective case series study from the perspective of clinical research, thus to ensure credibility and avoid bias of the results.