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Table 1 Patient demographics and baseline characteristics of Intention to treat analysis population

From: Mechanistically informed non-invasive peripheral nerve stimulation for peripheral neuropathic pain: a randomised double-blind sham-controlled trial

  Category Active (n = 38) Sham
(n = 38)
All patients
(n = 76)
Mechanistic study
(n = 19)#
Age   47.3 ± 15.9 53.6 ± 11.2 50.4 ± 14.0 61.8 ± 14.9
Gender Female 22 (58%) 18 (47%) 40 (53%) 9
  Male 16 (42%) 20 (53%) 36 (47%) 10
Duration Pain (months)   44 [27, 96] 48 [26, 72] 47 [27, 87] 61 [23,63]
Mechanism of Injury Nerve entrapment 1 (3%) 2 (5%) 3 (4%) 2 (11%)
Nerve injury  
 Surgery 29 (76%) 25 (66%) 54 (71%) 8 (42%)
 Other mech. Trauma 6 (16%) 7 (18%) 13 (17%) 6 (32%)
 Radiotherapy 2 (5%) 0 (0%) 2 (3%) 0 (0%)
 Medication 0 (0%) 1 (3%) 1 (1%) 0 (0%)
Post-herpetic neuralgia 0 (0%) 3 (8%) 3 (4%) 2 (11%)
Number pain meds   1.6 ± 1.5 1.7 ± 1.4 1.7 ± 1.4 1.8 ± 1.1
Pain medications+ General pain meds 18 (58%) 24 (69%) 42 (64%) 3 (16%)
  NSAIDs 9 (29%) 13 (37%) 22 (33%) 2 (11%)
  Opioids 9 (29%) 7 (20%) 16 (24%) 7 (37%)
  Anti-Epileptics 15 (48%) 20 (57%) 35 (53%) 10 (53%)
  Anti-Depressants 16 (52%) 11 (31%) 27 (41%) 6 (32%)
  Muscle relaxants 1 (3%) 2 (6%) 3 (5%) 0 (0%)
Baseline assessments     
 Primary Pain in last 7 days 7.2 ± 1.2 7.5 ± 1.4 7.3 ± 1.3 7.42 ± 1.3
 Variability pain*   0.85 ± 0.51 0.84 ± 0.44 0.85 ± 0.47 0.65 ± 0.55
 Secondary EQ VAS 51 ± 18 57 ± 25 54 ± 22 48 ± 27
  EQ-5D index 0.35 ± 0.23 0.34 ± 0.29 0.35 ± 0.26 0.27 ± 0.29
  BPI I 6.2 ± 1.9 6.4 ± 2.0 6.3 ± 1.9 6.3 ± 2.9
 Exploratory BPI W 8.4 ± 1.1 8.2 ± 1.4 8.3 ± 1.2 8.5 ± 0.9
  HADS anxiety 10.7 ± 4.3 10.4 ± 5.2 10.5 ± 4.8 9.8 ± 5.6
  HADS depression 9.3 ± 4.6 9.0 ± 4.5 9.1 ± 4.5 9.5 ± 5.7
  PESQ 24 ± 14 23 ± 14 24 ± 14 19.7 ± 13
  DMA mapped area 207 ± 192 175 ± 141 191 ± 168 204 ± 166
  NPSI total score 63 ± 15 61 ± 19 62 ± 15 53 ± 19
  1. Summary statistics are mean ± standard deviation, median [inter-quartile range] or number (percentage). There were no significant differences in any baseline measures between active and sham groups
  2. 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 scale anxiety subscale, HADS depression = Hospital anxiety scale depression subscale, PSEQ = Pain self-efficacy questionnaire, DMA mapped area = Dynamic allodynia mapped area, NPSI total = Neuropathic pain symptom inventory subscale total score
  3. *Measured by the standard deviation of the baseline daily pain scores in the week prior to randomisation
  4. +Patients could be on more than one type of pain medication. Percentage values may not add up to 100%
  5. # For mechanistic study the variables age, gender, duration of pain, mechanism of injury and information relating to medications were available for all 19 patients, but for all other outcomes, the numbers represent n = 15/19 available data sets