Ware 2010.

Study characteristics
Methods	Design: cross‐over Duration: each cross‐over period lasted 2 weeks Assessment: baseline and post‐cross‐over period Country: Canada
Participants	Pain condition: fibromyalgia Population: adults with fibromyalgia and self‐reported chronic insomnia Minimum pain intensity: no Inclusion criteria People with a diagnosis of fibromyalgia who had self‐reported chronic insomnia Exclusion criteria Severe physical comorbidities and psychotic disorders Total participants randomised: 32 Age in years (mean, SD): 49.5 (11.2) Gender: 26/32 were female Pain duration in years (mean, SD): NR
Interventions	Nabilone 0.5‐1.0 mg Synthetic cannabinoid Flexible titration: started at 0.5 mg/day for the first week, physician assessed and if patient could benefit from higher dose the dose was doubled for the second week to 1 mg/day. Amitriptyline 10‐20 mg TCA Flexible titration: started at 10 mg/day for the first week, physician assessed and if patient could benefit from higher dose the dose was doubled for the second week to 20 mg/day.
Outcomes	SAEs
Missing data methods	Unclear
Funding source	Pharmaceutical: supported by an unrestricted grant from Valeant (Canada) Inc.
Conflicts of interest	MAW and MAF have received honoraria from Valeant Canada for CME activities. YS and LJ have no conflicts to declare.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"The randomisation schedule was prepared (ralloc procedure, Stata version 8.0, Houston, TX) using randomly assigned block sizes ranging from 2 to 8."
Allocation concealment (selection bias)	Low risk	"The schedule was kept by the study pharmacist away from the investigators. Study subjects were consecutively assigned to treatment order by the study nurse based on the randomisation schedule. A coded script was given to the subject with instructions on the use of the allocated treatment. The subject then collected the medication from the study pharmacy and began taking the medication the same night."
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Identical opaque capsules for both nabilone and amitriptyline
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Self‐reported outcomes by blinded participants
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Unclear ‐ no missing data methods reported Attrition Total: 3/32 (9.4%) Attrition per arm NR
Selective reporting (reporting bias)	Low risk	All outcomes are prespecified in protocol on clinicaltrials.gov
Other bias	Low risk	No other sources of bias identified