Pulmonary Medicine / 2020 / Article / Tab 1

Research Article

The Effect of Smoking on COVID-19 Symptom Severity: Systematic Review and Meta-Analysis

Table 1

Newcastle-Ottawa scale for quality assessment and risk of bias.

StudyYearCase selection (max. 4)Comparability (max. 2)Exposure/outcome (max. 3)Total score

CDC report [4]20207
Chen Q [10]20206
Feng Y [11]20206
Goyal P [12]20205
Guan WJ [13]20206
Liu W [14]20207
Mo P [15]20206
Qi D [16]20207
Shi Y [17]20205
Wang R [18]20206
Wan S [19]20207
Yang X [20]20208
Yu X [21]20207
Zhang JJ [22]20207
Zhang R [23]20206
Zhou F [24]20207

Article of the Year Award: Outstanding research contributions of 2020, as selected by our Chief Editors. Read the winning articles.