Table 4.
Associations between PDQ-D total score/DSST score and functional outcomes at month 6
| Adjusted mean (SE)a | |||||||
|---|---|---|---|---|---|---|---|
| SDS total score | WPAI-SHP absenteeism | WPAI-SHP presenteeism | WPAI-SHP overall work impairment | WPAI-SHP activity impairment | EQ-5D Utility Index |
UPSA-B total scored |
|
| PDQ-D quartiles at month 2b | |||||||
| 0–9 | 5.21 (0.98) | 14.44 (5.07) | 5.90 (4.36) | 6.92 (4.98) | 18.93 (4.20) | 0.86 (0.02) | 75.04 (5.75) |
| 10–17 | 7.37 (0.87) | 15.38 (4.81) | 11.26 (4.22) | 13.54 (4.82) | 24.60 (4.38) | 0.83 (0.02) | 81.04 (5.77) |
| 18–30 | 8.98 (0.86) | 17.03 (4.56) | 19.31 (3.94) | 22.12 (4.49) | 27.97 (4.17) | 0.81 (0.02) | 79.59 (5.41) |
| 31–80 | 12.38 (0.80) | 26.07 (4.28) | 31.44 (3.75) | 35.72 (4.29) | 40.67 (4.28) | 0.75 (0.02) | 78.22 (5.25) |
| p-value | <0.001 | 0.031 | <0.001 | <0.001 | <0.001 | <0.001 | 0.282 |
| DSST score at month 2c | |||||||
| Within norm | 7.35 (1.33) | 15.32 (4.01) | 12.96 (5.07) | 14.53 (5.80) | 23.79 (3.61) | 0.83 (0.02) | 88.98 (2.87) |
| 1/3 to 2/3 SD below norm | 8.80 (1.55) | 14.86 (5.22) | 15.38 (5.85) | 17.89 (6.69) | 28.01 (4.29) | 0.79 (0.03) | 83.04 (3.52) |
| 2/3 to 1 SD below norm | 6.89 (1.65) | 33.91 (6.29) | 11.03 (7.22) | 14.85 (8.26) | 25.37 (4.33) | 0.83 (0.03) | 93.42 (4.93) |
| ≥1 SD below norm | 9.23 (1.44) | 19.05 (4.84) | 15.14 (5.46) | 17.55 (6.28) | 27.28 (3.92) | 0.80 (0.03) | 87.27 (4.77) |
| p-value | 0.108 | 0.027 | 0.840 | 0.810 | 0.415 | 0.021 | 0.108 |
Notes: ANCOVA based on a stepwise backward model selection with age, gender, region, month 2 HAM-D17, and month 2 PDQ-D total score/DSST score as forced factors. aLeast squares mean from the ANCOVA model. b0–9, n=135; 10–17, n=155; 18–30, n=140; 31–80, n=155. cWithin norm, n=360; 1/3 to 2/3 SD below norm, n=74; 2/3 to 1 SD below norm, n=53; or 1 SD or more below norm, n=111. dUPSA-B assessed in a subsample (n=200).
Abbreviations: ANCOVA, analysis of covariance; DSST, Digit Symbol Substitution Test; EQ-5D, European Quality of Life Questionnaire – 5 Dimensions; HAM-D17, Hamilton Depression Rating Scale – 17 items; PDQ-D, Perceived Deficits Questionnaire-Depression; SDS, Sheehan Disability Scale; SE, standard error; UPSA-B, University of San Diego Performance-based Skills Assessment – Brief; WPAI-SHP, Work Productivity and Activity Impairment Questionnaire – Specific Health Problems Questionnaire.