Table 3 Goodness-of-fit statistics for the SF-12 mental health (MH) and physical health (PH) sub-scales with and without correlated residual variances, stratified by type of joint replacement
From: Differential item functioning of the SF-12 in a population-based regional joint replacement registry
Model | Joint Type | RMSEA (90% CI) | CFI | TLI | WRMR |
|---|---|---|---|---|---|
MH Sub-scale | |||||
 No residual variance correlations | THA | 0.22 (0.21, 0.23) | 0.97 | 0.94 | 4.77 |
TKA | 0.21 (0.21, 0.22) | 0.97 | 0.95 | 5.18 | |
 With residual variance correlations: items M1 and M2, M3 and M5 | THA | 0.15 (0.14, 0.15) | 0.99 | 0.97 | 2.47 |
TKA | 0.14 (0.13, 0.15) | 0.99 | 0.98 | 2.76 | |
 With residual variance correlations: items M1 and M2, M3 and M5, M3 and M4, M4 and M6 | THA | 0.05 (0.04, 0.07) | 1.00 | 1.00 | 0.62 |
TKA | 0.03 (0.02, 0.04) | 1.00 | 1.00 | 0.38 | |
PH Sub-scale | |||||
 No residual variance correlations | THA | 0.19 (0.18, 0.20) | 0.98 | 0.97 | 4.49 |
TKA | 0.15 (0.14, 0.15) | 0.98 | 0.97 | 3.95 | |
 With residual correlations: items P2 and P3, P4 and P5 | THA | 0.03 (0.02, 0.04) | 1.00 | 1.00 | 0.61 |
TKA | 0.02 (0.01, 0.03) | 1.00 | 1.00 | 0.52 | |