| Methods |
Double‐blind placebo‐controlled cross‐over trial. 2 x 4‐week treatment periods with a 2‐week washout |
| Participants |
30 adults with atypical facial pain of intensity at least 3 on an 11‐point scale. Median age 52 years (range 38‐66 years). Gender data were reported for the 18 participants for whom data were analysed (6 men and 12 women). The study was conducted in Finland |
| Interventions |
Venlafaxine 37.5‐75 mg/day vs. placebo. All participants took 37.5 mg for 2 weeks and were then allowed to regulate the dose themselves. 17 took venlafaxine 75 mg for a second 2 weeks and 1 took 37.5 mg. Paracetamol and NSAIDs were also permitted as escape medications |
| Outcomes |
Participant‐reported VAS‐PI (0‐100), VRS‐PI (8‐point scale), VRS‐PR, and VAS‐PR (0‐50) were the primary outcome measures. VAS‐PI, VAS‐PI, and VRS‐PI did not differ significantly between groups. VRS‐PR reported as significantly greater during venlafaxine period vs. placebo. Increased use of escape medication in placebo groups vs. venlafaxine but not well described. No significant difference between groups in anxiety (STAI) or depression (BDI) |
| Notes |
10 drop‐outs including 8 due to adverse effects. 6 in venlafaxine arm (nausea 5 and fatigue 1). 2 in placebo arm (rash 1 and dizziness 1). 2 participants excluded due to non‐compliance |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Low risk |
Randomisation was performed by Wyeth‐Lederle, who supplied the drug and placebo capsules 'using computer‐generated numbers' |
| Allocation concealment (selection bias) |
Low risk |
Participants were allocated consecutively |
| Blinding of participants and personnel (performance bias)
All outcomes |
Low risk |
Identical capsules were supplied by a pharmaceutical company (Wyeth‐Lederle) |
| Blinding of outcome assessment (detection bias)
All outcomes |
Low risk |
'The randomization code was not opened during the trial' and along with plasma concentration data were 'kept separate from investigators carrying out the assessments until the database was closed' |
| Incomplete outcome data (attrition bias)
All outcomes |
High risk |
Completer analysis was employed. Only 20/30 participants completed the trial |
| Size |
High risk |
< 50 participants per treatment arm |
