Vranken 2011.

Methods	Stratified, randomised, double‐blind, placebo‐controlled, parallel group study of patients with severe central neuropathic pain of more than 6 months duration from cerebrovascular or spinal cord lesions
Participants	48 participants aged 18 years or older with > 6 month severe neuropathic pain from cord or cerebrovascular cause, > 6 on visual analogue scale (VAS) (10 points), which started after sustaining the lesion and with the distribution of pain concomitant with the somatosensory system involvement. The trial allowed other medication if doses were stable for 6 weeks, except other antidepressants, which had to be stopped more than 30 days prior to receiving study medication
Interventions	Duloxetine or placebo for 8 weeks. Duloxetine 60 mg at start. Increased if participants did not meet criteria of > 1.8 points improvement on VAS. At week 8 and study end 15 participants on 120 mg and 8 participants on 60 mg
Outcomes	Primary outcome Pain intensity on a 10‐point VAS measured a baseline and weekly for the 8 weeks of the study. The final mean pain score was an average of 9 VAS scores measured over 72 hours in the last 3 days of the study Secondary outcomes Pain disability Index EQ‐5D Short Form 36 Health Survey (SF‐36) (beginning and end) Patient Global Impression of Change (PGIC) (end of study only) Quantitative sensory testing Adverse events
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Simple computerised random sampling (clorandm.exe) assigned study codes N = 1 to the placebo or duloxetine arm. Consecutive participants who met inclusion criteria were randomly assigned to treatment with flexible dose placebo or flexible dose duloxetine
Allocation concealment (selection bias)	Low risk	The association between type of treatment and study code was only known to the Department of Epidemiology, Biostatistics and Bioinformatics and the hospital pharmacy department
Blinding (performance bias and detection bias) All outcomes	Low risk
Incomplete outcome data (attrition bias) All outcomes	Low risk
Selective reporting (reporting bias)	Low risk
Other bias	Low risk