Fig. 4From: Smoking prevalence among hospitalized COVID-19 patients and its association with disease severity and mortality: an expanded re-analysis of a recent publicationRandom-effects meta-analysis of the association between smoking and COVID-19 severity with studies stratified by diabetes prevalence (< 15% and ≥ 15%). Boxes represent odds ratios (ORs) and their size represent the studies weight, while lines represent the 95%CIBack to article page