Figure 2: Pooled estimate of odds ratio (OR) and 95% confidence intervals (CIs) of risk of lung cancer in Helicobacter pylori infected patients. Squares indicate OR in each study. The square size is proportional to the weight of the corresponding study in the metaanalysis; the length of horizontal lines represents the 95% CI. The diamond indicates the pooled OR and 95% CI (randomeffects model). 
