COVID-19(94) supplementary material(62) SARS-CoV-2(46) pandemic(44) age(38) Mortality(36) Infection(36) COVID-19 pandemic(30) conducted(29) risk(29) death(29) Factor(28) country(26) Epidemiology(26) participant(20) Intervention(20) deaths(19) Symptom(19) proportion(18) 95% CI(18) public health(18) individual(17) COVID-19 mortality(17) reported(17) intensive care(17) Characteristics(16) Hospitalization(16) approach(16) measure(16) less(16)