ABSTRACT
BACKGROUND: Since December 2019, there have been cases of infectious pneumonia of unknown cause in Wuhan, Hubei Province, China. On January 12, 2020, the World Health Organization (WHO) named it COVID-19. There are few studies on the clinical characteristics of patients with COVID-19, and results vary widely in sample sizes. METHODS: Chinese and English databases were searched with "Infectious pneumonia", "COVID-19", "CT", "SARS-COV-2", and "Diagnose" as keywords. Rev Man 5.3 software provided by the Cochrane system was used to assess the quality of the included literature. RESULTS: Of the 18 included studies, ground-glass shadow was the most common computed tomography (CT) sign [95% confidence interval (CI): 0.79-0.97], followed by thickening of the blood vessels (95% CI: 0.63-0.78), and pleural thickening (95% CI: 0.02-0.15). Of the 18 studies, 12 reported that the lesions were externally subpleural (95% CI: 0.132-0.173), and 6 reported that the lesions were distributed in a single lobe (95% CI: 0.598-0.841). The heterogeneity test results showed that the morphology of the lesions was cord-like (95% CI: 0.092-0.172), grid-like (95% CI: 0.152-0.193), patchy (95% CI: 0.192-0.313), and nodular (95% CI: 0.591-0.745). DISCUSSION: Ground-glass opacity was a typical CT manifestation for patients with infectious pneumonia, and CT signs were instrumental in diagnosing this disease.