Rintala 2007.

Study characteristics
Methods	Design: cross‐over Duration: each cross‐over period was 8 weeks Assessment: baseline and post‐cross‐over period Country: USA
Participants	Pain condition: chronic neuropathic pain following spinal cord injury Population: adults with a spinal cord injury at least 12 months ago with chronic neuropathic pain Minimum pain intensity: ≥ 5 on 0‐10 scale Inclusion criteria Aged 18‐70 Spinal cord injury occurred at least 12 months before entering the study At least 1 chronic (6 months) pain component characteristic of neuropathic pain At least 1 neuropathic pain component rated as at least 5 on a 0‐10 scale Exclusion criteria Physical and mental health comorbidities Total participants randomised: 38 Age in years (completers; mean, SD): 42.6 (12.6) Gender (completers): 2/38 were female Pain duration in years (completers; mean, SD): 7.3 (7.7)
Interventions	Gabapentin ≤ 3600 mg Anticonvulsant Forced titration to maximum tolerated dose Matched dosing schedule Amitriptyline ≤ 150 mg TCA Forced titration to maximum tolerated dose Matched dosing schedule Placebo (diphenhydramine ≤ 75 mg) Active placebo ‐ antihistamine Forced titration to fixed dose Matched dosing schedule
Outcomes	Pain intensity Moderate pain relief Withdrawal
Missing data methods	Completer‐only analysis
Funding source	Non‐pharmaceutical: supported by the Department of Veterans Affairs, Veterans Health Administration, Rehabilitation Research and Development Service (grant no. B2573R)
Conflicts of interest	"No commercial party having a direct financial interest in the results of the research supporting this article has or will confer a benefit upon the author(s) or upon any organisation with which the author(s) is/are associated"
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	The order of this assignment within the sets of 6 was based on a table of random numbers, and varied from set to set.
Allocation concealment (selection bias)	Unclear risk	Allocation procedure not specified
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Matched dosing regime, active comparator used as placebo, and identical capsules for medication
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Self‐reported outcomes from blinded participants
Incomplete outcome data (attrition bias) All outcomes	High risk	Completer analysis only. High levels of attrition Attrition Total: 16/38 (42.1%) Gabapentin ≤ 3600 mg: 12/38 (31.6%) Amitriptyline ≤ 150 mg: 10/38 (26.3%) Placebo: 13/38 (34.2%) As this is a cross‐over study, some participants only withdrew from one period of the study, not the study as a whole, therefore, the numbers of participants withdrawing per arm does not match the total numbers of participants withdrawing.
Selective reporting (reporting bias)	Unclear risk	No protocol or trial registration found
Other bias	Low risk	No other sources of bias identified