Objective: The ongoing novel coronavirus disease 2019 (COVID-19) is the main cause of morbidity and mortality due to its contagious nature and absence of vaccine and treatment. Although there are considerable primary studies that reported extremely variable case fatality rate (CFR) of COVID-19, there is no review study that attempted to estimate CFR of COVID-19. The current systematic review and meta-analysis was aimed to estimate the pooled CFR of COVID-19.
Methods: Electronic databases: PubMed, Science Direct, Scopus and Google Scholar were searched to retrieve the eligible primary studies that reported CFR of COVID-19. Keywords: ("COVID-19"OR "COVID-2019" OR "severe acute respiratory syndrome coronavirus 2"OR "severe acute respiratory syndrome coronavirus 2" OR "2019-nCoV" OR "SARS-CoV-2" OR "2019nCoV" OR (("Wuhan" AND ("coronavirus" OR "coronavirus")) AND (2019/12[PDAT] OR 2020[PDAT]))) AND ("mortality "OR "mortality" OR ("case" AND "fatality" AND "rate") OR "case fatality rate") were used as free text and MeSH term in searching process. Random-effects model used to estimate the CFR in this study. I2 statistic, Cochran’s Q test and T2 were used to assess the available heterogeneity between included studies.
Results: The overall pooled CFR of COVID 19 was 10.0 %( 95% CI: 8.0-11.0); P<0.001; I2 = 99.7). The pooled CFR of COVID 19 in general population was 1.0% (95% CI: 1.0–3.0); P<0.001; I2 = 94.3), while in hospitalized patients was 13.0 % (95% CI: 9.0–17.0); P<0.001, I2 = 95.6). The pooled CFR in patients admitted in intensive care unit (ICU) was 37.0 % (95% CI: 24.0–51.0); P<0.001, I2 = 97.8) and in patients older than 50 years was 19.0 % (95% CI: 13.0–24.0); P<0.001; I2 = 99.8).
Conclusion: The present review results highlighted the need of transparency in testing and reporting policies and denominators used in CFR estimation. It is also necessary reporting the cases age, sex and the comorbidity distribution of all patients which important in comparing the CFR among different segments of population.
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