Table 2.
Study outcomes (intention to treat)
| Group | N | Baseline Mean ± SD |
3 months Mean ± SD |
Trt effect* Mean (95% CI) |
P-value | |
|---|---|---|---|---|---|---|
| Primary outcome | ||||||
| Average NRS (over 7 days) | Active | 31 | 7.1 ± 1.3 | 6.2 ± 1.9 | − 0.3 (− 1.0, 0.3) | |
| Sham | 34 | 7.3 ± 1.4 | 6.7 ± 1.7 | 0 | 0.30 | |
| Secondary outcomes | ||||||
| EQ VAS | Active | 31 | 48 ± 18 | 61 ± 20 | 10 (0, 19) | |
| Sham | 34 | 57 ± 25 | 56 ± 24 | 0 | 0.05 | |
| EQ-5D Index | Active | 31 | 0.36 ± 0.25 | 0.46 ± 0.29 | 0.04 (− 0.06, 0.14) | |
| Sham | 34 | 0.35 ± 0.29 | 0.41 ± 0.31 | 0 | 0.40 | |
| BPI I | Active | 31 | 6.3 ± 1.9 | 4.9 ± 2.6 | − 0.9 (− 1.7, 0.0) | |
| Sham | 34 | 6.3 ± 2.0 | 5.8 ± 2.3 | 0 | 0.06 | |
| Exploratory outcomes | ||||||
| BPI worst pain | Active | 31 | 8.4 ± 1.0 | 7.0 ± 1.9 | − 0.8 (− 1.6, 0.1) | |
| Sham | 34 | 8.0 ± 3.0 | 7.4 ± 1.9 | 0 | 0.07 | |
| HADS anxiety | Active | 31 | 11.0 ± 4.7 | 9.2 ± 5.1 | − 0.9 (− 2.3, 0.5) | |
| Sham | 34 | 10.6 ± 5.1 | 9.7 ± 4.5 | 0 | 0.22 | |
| HADS depression | Active | 31 | 9.4 ± 4.9 | 8.3 ± 4.9 | − 1.1 (− 2.4, 0.3) | |
| Sham | 34 | 9.0 ± 4.5 | 9.0 ± 5.0 | 0 | 0.13 | |
| PESQ | Active | 31 | 23 ± 13 | 28 ± 15 | 1 (− 2, 5) | |
| Sham | 34 | 24 ± 15 | 27 ± 16 | 0 | 0.46 | |
| DMA mapped area (cm2) | Active | 31 | 211 ± 204 | 173 ± 215 | − 74 (− 126, − 22) | |
| Sham | 34 | 180 ± 145 | 215 ± 202 | 0 | 0.006 | |
| NPSI total | Active | 31 | 63 ± 15 | 52 ± 19 | − 5 (− 12, 2) | |
| Sham | 34 | 59 ± 18 | 55 ± 16 | 0 | 0.13 | |
N: the number of patients with both baseline and end of treatment outcomes; Average NRS: Average pain intensity; EQ VAS: EuroQol visual analogue score; EQ-5D Index: EQ-5D-5L index score (utility); BPI I: Brief pain inventory interference subscale; BPI W: Brief pain inventory worst pain intensity; HADS anxiety: Hospital anxiety and depression scale anxiety subscale; HADS depression: depression subscale; PSEQ: Pain self-efficacy questionnaire; DMA mapped area: Dynamic allodynia mapped area; NPSI total: Neuropathic pain symptom inventory subscale total score
* Trt effect = Treatment effect is difference in outcome between treatment groups, adjusted for outcome at baseline. All analyses using ANCOVA
** Total costs (mean and 95% confidence intervals generated from 1,000 bootstrap replications) relate to the 3-month periods prior to baseline and follow-up and exclude the cost of device.