Protocol and search strategy
The study was conducted following the Preferred Reporting Items for Systematic review and Meta-Analysis[14]. Ethics committee approval is not applicable for this study. The search strategy was developed by experts in respiratory medicine. Search terms were as follows: (“COVID-19” or “novel coronavirus-infected pneumonia” or “NCIP” or “SARS-CoV-2” or “2019-nCoV”) and (“Clinical characteristics” or “CT manifestations” or “symptom” or “epidemiological characteristics” or “clinical features”) (e-Table 1). Two reviewers (Mingjin Y. and Yan Z.) independently searched PubMed, China National Knowledge Infrastructure (CNKI), EMBASE, and Cochrane Library from May 05, 2020 to May 27, 2020. Articles in Chinese or English were included.