Methods	Randomised, double-blind, placebo-controlled, cross-over, not enriched. No imputation method mentioned Titration over 3 days to 900 mg, then fixed dose for remainder of 6-week period; 3 week washout, then cross-over
Participants	Painful diabetic neuropathy 1 to 5 years, pain ≥ moderate for over 3 months. N = 40, mean age 62 years, 23% women. Pain intensity at randomisation ≥ 40/100, initial pain intensity not reported
Interventions	Gabapentin 900 mg, n = 19 (first phase) Placebo, n = 21 (first phase) Medication for diabetes control remained stable during study. Stable doses of NSAID or narcotics allowed
Outcomes	Pain relief at end of treatment (4-point global score) moderate or excellent Adverse events
Notes	Oxford Quality Score: R = 1, DB = 1, W = 0, Total = 3 Sponsored by Warner Lambert/Parke-Davis Note: no separate data for first period, small group sizes, non standard global scale
Risk of bias
Item	Authors’ judgement	Description
Allocation concealment?	Unclear	Not reported
Blinding? All outcomes	Unclear	Not reported
Incomplete outcome data addressed? Efficacy	Unclear	Imputation not mentioned
Size Efficacy	No	40 randomised
Study duration Efficacy	Unclear	6-week period
Outcomes reported	Unclear	Moderate or excellent pain relief