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.