Comparison of unblinded and blinded patients at baseline
| Variable | Unblinded | Blinded | Unadjusted P |
|---|---|---|---|
| No. of patients (%) | 131 (53.3%) | 115 (46.7%) | |
| Mean age | 42.8 (SD = 10.3) | 43.3 (SD = 10.6) | .733 |
| No. of women (%) | 79 (55.6%) | 63 (44.4%) | .382 |
| No. of people of color (%) | 40 (54.8%) | 33 (45.2%) | .732 |
| Mean years of education | 14.5 (SD = 2.9) | 15.0 (SD = 2.7) | .087 |
| Mean no. of sick days | 2.4 (SD = 4.1) | 2.4 (SD = 4.2) | .682 |
| No. with radiculopathy (%) | 76 (58.0%) | 74 (49.3%) | .310 |
| Mean Roland score | 13.9 (SD = 5.2) | 12.4 (SD = 5.8) | .054 |
| Mean VPAS for average pain | 5.3 (SD = 1.8) | 5.2 (SD = 2.0) | .867 |
| Mean VPAS for worst pain | 8.8 (SD = 1.4) | 8.3 (SD = 2.1) | .180 |
| Mean self-efficacy pain | 55.4 (SD = 21.7) | 59.3 (SD = 22.9) | .165 |
| Mean self-efficacy other | 60.5 (SD = 21.6) | 64.2 (SD = 21.0) | .186 |
| Mean FAQ physical activity | 17.0 (SD = 5.8) | 17.4 (SD = 5.5) | .517 |
| Mean FAQ work | 14.4 (SD = 10.9) | 14.4 (SD = 10.8) | .975 |
| Mean SF-36: PF | 45.3 (SD = 25.1) | 47.6 (SD = 26.5) | .517 |
| Mean SF-36: RP | 17.4 (SD = 30.7) | 22.8 (SD = 35.1) | .287 |
| Mean SF-36: BP | 28.9 (SD = 30.7) | 33.7 (SD = 21.5) | .093 |
| Mean SF-36: GH | 73.4 (SD = 18.3) | 74.7 (SD = 16.1) | .723 |
| Mean SF-36: VT | 41.5 (SD = 22.0) | 46.9 (SD = 20.2) | .032 |
| Mean SF-36: SF | 57.4 (SD = 32.5) | 62.5 (SD = 30.3) | .252 |
| Mean SF-36: RE | 74.9 (SD = 38.7) | 77.3 (SD = 35.7) | .904 |
| Mean SF-36: MH | 75.7 (SD = 20.4) | 78.3 (SD = 16.3) | .698 |
Note:—SD indicates standard deviation; VPAS, visual pain analog scale; FAQ, fear avoidance questionnaire; SF, short form; PF, physical functioning; RP, role-physical; BP, bodily pain; GH, general health; VT, vitality; SF, social functioning; RE, role-emotional; MH, mental health.