Figure 4From: Systematic review with meta-analysis of the epidemiological evidence relating smoking to COPD, chronic bronchitis and emphysema Forest plot of ever smoking of any product and CB-part 2. This is a continuation of Figure 3, presenting the remaining individual study data included in the main meta-analysis for CB shown in Table 5. Also shown are the combined random-effects estimates. These are represented by a diamond of standard height, with the width indicating the 95% CI.Back to article page