Table 5.
Subgroup analysis-comparison of baseline and follow-up outcomes among pain improvement subgroup* and remaining sample.
| Patient-reported Outcome, mean (SD) | Baseline | Follow-up | Mean Change (95% CI) | P value | |||
|---|---|---|---|---|---|---|---|
| BPI-SF Pain Severity Index† | |||||||
| ≥2pt improvement | 5.6 (1.3) | 3.1 (1.8) | -2.43 (-3.26, -1.61) | <0.001 | |||
| <2pt improvement | 5.2 (2.0) | 5.5 (2.1) | 0.25 (-0.06, 0.55) | 0.111 | |||
| BPI-SF Pain Interference Index† | |||||||
| ≥2pt improvement | 6.8 (1.7) | 3.4 (2.4) | -3.35 (-4.89, -1.81) | 0.001 | |||
| <2pt improvement | 5.7 (2.5) | 5.6 (2.3) | -0.12 (-0.52, 0.29) | 0.568 | |||
| WPAI Activity Impairment† | |||||||
| ≥2pt improvement | 59.1 (25.9) | 50.0 (23.2) | -9.09 (-31.86, 13.68) | 0.395 | |||
| <2pt improvement | 58.3 (24.9) | 61.2 (27.5) | 2.33 (-2.14, 6.80) | 0.301 | |||
| MOS-SS Overall Sleep Problems Index† | |||||||
| ≥2pt improvement | 62.4 (13.9) | 51.0 (17.5) | -11.41 (-23.49, 0.66) | 0.061 | |||
| <2pt improvement | 57.6 (16.0) | 53.0 (16.4) | -4.15 (-7.78, -0.51) | 0.026 | |||
| EQ-5D | |||||||
| ≥2pt improvement | 0.59 (0.21) | 0.68 (0.20) | 0.09 (-0.05, 0.24) | 0.189 | |||
| <2pt improvement | 0.64 (0.19) | 0.65 (0.19) | 0.02 (-0.03, 0.06) | 0.518 | |||
| SF-12 Physical Component Summary† | |||||||
| ≥2pt improvement | 37.0 (8.3) | 38.6 (8.0) | 1.67 (-3.75, 7.09) | 0.508 | |||
| <2pt improvement | 32.1 (11.1) | 33.3 (11.3) | 1.51 (-0.41, 3.43) | 0.121 | |||
Abbreviations: BPI-SF, Brief Pain Inventory-Short Form; EQ-5D, EuroQol 5 dimensions, 3 levels; MOS-SS, Medical Outcomes Study-Sleep Scale; pt, point; SD, standard deviation; SF-12, 12-item Short-Form Health Survey; WPAI, Work Productivity and Activity Impairment scale. *These patients experienced clinically meaningful (i.e., at least 2.0 points) improvement in average pain severity over the past 7 days between Baseline and Follow-up assessments. †A total of 76 fibromyalgia patients (11 with ≥2 point improvement, 65 with <2 point improvement) attended the site visit at Follow-up, but 5 patients in the subgroup with <2 point improvement did not complete the patient questionnaire following the site visit.