Study selection and characteristics
Our search strategy yielded a total of 2087 published studies. After further screening by reading the title, abstract, and/or full text, 9 studies met the inclusion criteria for further analysis. The 9 included studies enrolled 1,795 patients. The flowchart is shown in Fig.1. The 9 included studies were published from January 24, 2020 to February 22, 2020. Population sizes ranged from 29 to 1,099 patients. All patients were admitted to the hospital for treatment. Among the studies, eight were retrospective analysis and one was a descriptive study. Five reported clinical symptoms, complications, computed tomography (CT) images, and laboratory findings. Seven reported clinical symptoms and CT images. One studies only provided the information of chronic medical illness, symptoms, and complications (Table 1).
Each included study was given a quality score (0 to 8) based on fulfillment of the quality criteria. Of the included trials, one study was assessed as 7 (range 0-8). Seven studies were assessed as 5. One was assessed as 4 (e-Table 2).