Association between GDF5 rs143383 polymorphism and knee osteoarthritis: an updated meta-analysis based on 23,995 subjects

Table 4 Identifying the source of heterogeneity by control type and knee OA definition

Subgroup	C vs. T		CC vs. TT		CT vs. TT		CC/CT vs. TT		CC vs. CT/TT
	P _h	I ²(%)	P _h	I ²(%)	P _h	I ²(%)	P _h	I ²(%)	P _h	I ²(%)
Source of controls
HB	0.196	29.1	0.681	0.0	0.013	60.8	0.032	54.4	0.703	0.0
PB	0.051	46.6	0.233	23.7	0.006	62.9	0.005	64.0	0.511	0.0
Knee OA definition
Radiographic	0.043	48.3	0.654	0.0	0.003	68.1	0.002	68.9	0.874	0.0
TKR	0.206	30.5	0.132	41.0	0.187	33.3	0.184	33.6	0.153	38.0

HB hospital-based, PB population-based, TKR total knee replacement, P _h, P value of Q-test for heterogeneity test.

ISSN: 1471-2474