Fig. 4
From: The association between apolipoprotein E and gallstone disease: an updated meta-analysis
Forest plot for meta-analysis of the association of APOE E4 with GSD risk after including the study by Boland et al. Each study is represented by a square whose area is proportional to the weight of the study. The overall effect from meta-analysis is represented by a diamond whose width represents the 95% CI for the estimated odds ratio (OR). GSD, gallstone disease; OR, odds ratio; CI, confidence interval