Figure 1.

Forest plot of study-specific estimates and fixed-effects summary OR estimates and 95% CI for the association between the rs143383 polymorphism of the GDF5 gene and knee osteoarthritis (OA) in current and previously published studies. The summary statistics and corresponding p values for all studies and for sensitivity analyses excluding studies out of Hardy–Weinberg equilibrium (HWE; indicated by *) and/or Asian studies are shown. The between-study heterogeneity I² and the respective 95% CI are also included.