Pulmonary Medicine / 2020 / Article / Fig 3

Research Article

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

Figure 3

(a) Comparison of smoking status in severe COVID-19 patients. (b) Funnel plot for the meta-analysis of smoking among severe COVID-19 patients. (c) Comparison of smoking status among severe COVID-19 patients after the exclusion of a study by Zhang et al. [23]. (d) Funnel plot for the meta-analysis of smoking among severe COVID-19 patients after the exclusion of a study by Zhang et al. [23].
(a)
(b)
(c)
(d)

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