Table 2.
Baseline patient characteristics*
| Variable | SMT 0 | SMT 6 | SMT 12 | SMT 18 |
|---|---|---|---|---|
| Demographic | ||||
| Age (years) | 40.9 (14.1) | 41.4 (14.8) | 41.8 (14.0) | 41.2 (13.8) |
| Male | 51% | 51% | 51% | 48% |
| Non-white or Hispanic | 14% | 18% | 11% | 16% |
| Married | 37% | 28% | 41% | 36% |
| College degree | 58% | 63% | 51% | 53% |
| Annual income<$20,000 | 31% | 27% | 19% | 28% |
| Smoker | 17% | 13% | 6% | 8% |
| Confidence in treatment success (0 extremely doubtful – 6 extremely certain) | ||||
| Spinal manipulation (6-point Likert scale) | 3.6 ( 1.2) | 3.8 ( 1.1) | 3.7 ( 1.2) | 3.8 ( 1.1) |
| Light massage (6-point Likert scale) | 3.4 ( 1.2) | 3.5 ( 1.2) | 3.4 ( 1.2) | 3.5 ( 1.2) |
| Previous treatment experience | ||||
| Spinal manipulation | 71% | 70% | 74% | 72% |
| Massage | 52% | 56% | 43% | 54% |
| Baseline health | ||||
| Pain (100-point MVK scale) | 52.2 ( 16.3) | 51.0 ( 18.2) | 51.6 ( 17.5) | 51.5 ( 16.8) |
| Disability (100-point MVK scale) | 45.2 ( 21.8) | 44.8 ( 24.0) | 46.1 ( 23.4) | 45.2 ( 21.8) |
| QALY score (EQ-5D) | 0.76 ( 0.11) | 0.74 ( 0.11) | 0.76 ( 0.09) | 0.77 ( 0.07) |
| Costs (4 wks preceding baseline) | ||||
| Treatment ($) | 5.5 ( 13.5) | 15.2 ( 69.2) | 8.0 ( 28.0) | 11.7 ( 34.7) |
| Treatment + cost of lost productivity($) | 599.0 (645.8) | 546.1 (591.0) | 553.1 (603.5) | 533.7 (581.4) |
*
Mean (SD) or %.