Table 4.
Correlations, Mean Differences, and Standard Deviations of Actual Versus Linked PROMIS Depression T Scores
| Linking method/instrument | Correlation | Mean difference | SD of differences |
|---|---|---|---|
| CES-D | |||
| IRT pattern scoring | .84 | 0.31 | 5.46 |
| IRT cross-walk scoring | .82 | 0.09 | 5.78 |
| EQP, SM = 0.0 | .81 | 0.03 | 5.93 |
| EQP, SM = 0.3 | .80 | 0.30 | 6.20 |
| EQP, SM = 1.0 | .79 | 0.42 | 6.46 |
| PHQ-9 | |||
| IRT pattern scoring | .83 | 0.36 | 6.34 |
| IRT cross-walk scoring | .81 | 0.43 | 6.73 |
| EQP, SM = 0.0 | .80 | 0.18 | 6.88 |
| EQP, SM = 0.3 | .80 | 0.06 | 6.80 |
| EQP, SM = 1.0 | .80 | 0.08 | 6.82 |
| BDI-II | |||
| IRT pattern scoring | .87 | 0.21 | 5.87 |
| IRT cross-walk scoring | .86 | 0.21 | 6.01 |
| EQP, SM = 0.0 | .86 | 0.14 | 6.00 |
| EQP, SM = 0.3 | .86 | 0.18 | 6.00 |
| EQP, SM = 1.0 | .86 | 0.16 | 6.02 |
Note. PROMIS = Patient-Reported Outcomes Measurement Information System; IRT = item response theory; CES-D = Center for Epidemiologic Studies Depression Scale; PHQ-9 = 9-item Patient Health Questionnaire; BDI-II = Beck Depression Inventory–II; EQP = equipercentile; SM postsmoothing.