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Association of tobacco smoking history with severe COVID‐19. (a) Distribution of nonsmokers and smokers in nonsevere, ICU recovery and death. (b) Statistical significance of smoking risk where two‐tailed Fisher’s exact tests were used for this study. (c) Forest plot showing 2.5‐fold risk by fixed effect model (random effect model: OR = 2.81, 95% CI 1.78–4.45, Z = 4.41, P < 0.0001). (d) Funnel plot showing no publication bias.
