Possible Predictors of Response for Nonresponders (n = 94, 52%) and Responders (n = 86, 49%) Receiving Placebo (n = 180).
| Variable | Nonresponders | Responders | Wald’s t (P Value) | ||
|---|---|---|---|---|---|
| No. | % | No. | % | ||
| Demographics | |||||
| Sex (female) | 45 | 48 | 54 | 63 | 4.42 (.04) |
| Age cohort >59 y | 64 | 68 | 52 | 61 | 0.95 |
| Ethnicity (majority) | 74 | 79 | 70 | 81 | 4.94 |
| Married | 44 | 47 | 55 | 64 | 4.72 (.03) |
| Employed | 33 | 35 | 32 | 37 | 0.08 |
| Income, y <$20,000 | 42 | 45 | 41 | 48 | 0.29 |
| Veteran | 29 | 31 | 18 | 21 | 3.24 (.07) |
| Dysthymia | 54 | 57 | 38 | 44 | 2.04 |
| Education <13 y | 49 | 52 | 35 | 41 | 2.70 (.10) |
| Sites | 4.94 | ||||
| Lebanon | 27 | 29 | 31 | 36 | |
| Pittsburgh | 11 | 12 | 17 | 20 | |
| San Antonio | 25 | 26 | 14 | 16 | |
| Seattle | 31 | 33 | 24 | 28 | |
| Mean | SD | Mean | SD | ||
| Patient beliefs | |||||
| Biological beliefs | 3.4 | 1.1 | 3.0 | 1.2 | 4.88 (.03) |
| Psychological beliefs | 3.7 | 0.9 | 3.4 | 1.0 | 2.74 (.10) |
| Clinical | |||||
| Duke Severity of Illness | 21.7 | 13.8 | 19.4 | 13.2 | 0.33 |
| NEO—Neuroticism Scale | 3.1 | 0.7 | 2.9 | 0.6 | 5.04 (.02) |
| SCL scales | |||||
| Depression | 1.6 | 0.6 | 1.3 | 0.6 | 8.04 (.005) |
| Somatization | 1.1 | 0.8 | 0.9 | 0.6 | 3.73 (.05) |
| Anxiety | 1.0 | 0.7 | 0.8 | 0.6 | 8.04 (.005) |
| Hostility | 0.8 | 0.8 | 0.6 | 0.6 | 2.52 (.10) |
| Interpersonal sensitivity | 1.1 | 0.8 | 0.8 | 0.7 | 8.83 (.003) |
| SF-36 | |||||
| General health | 50.4 | 22.9 | 58.2 | 20.6 | 5.04 (.02) |
| Physical function | 57.0 | 30.7 | 66.0 | 27.0 | 2.38 |
| Role physical | 32.0 | 35.8 | 44.3 | 42.4 | 3.64 (.06) |
| Role emotional | 30.5 | 37.3 | 42.3 | 39.1 | 3.72 (.05) |
| Pain | 47.0 | 24.9 | 57.0 | 22.5 | 7.42 (.006) |
| Vitality | 30.1 | 19.2 | 36.6 | 19.5 | 5.24 (.02) |
| Mental health | 52.6 | 16.3 | 57.0 | 18.3 | 4.64 (.03) |
| Social function | 54.7 | 24.7 | 64.6 | 22.7 | 6.75 (.009) |
SCL = Hopkins Symptom Checklist-57 scales, SF-36 = Medical Outcomes Study Short-Form 36 scale.