Gilron 2016.

Study characteristics
Methods	Design: cross‐over Duration: 6 weeks Assessment: baseline and post‐intervention Country: Canada
Participants	Pain condition: fibromyalgia Population: people with fibromyalgia Minimum pain intensity: ≥ 4 on 0‐10 VAS Inclusion criteria Aged 18‐70 Fibromyalgia that matches the ACR criteria ≥ 4 on 0‐10 pain intensity VAS Exclusion criteria Physical health comorbidity Severe mood disorder Total participants randomised: 41 Age in years (median, range): 56 (20‐71) Gender: 36/41were female Pain duration in years (mean, SD): NR
Interventions	Placebo n = 41 Inert Identical appearance and matched dosing schedule Double‐dummy design Pregabalin ≤ 450 mg n = 41 Anticonvulsant Forced titration to maximum tolerated dose or ceiling dose Double‐dummy design Duloxetine ≤ 120 mg n = 41 SNRI Forced titration to maximum tolerated dose or ceiling dose Double‐dummy design Pregabalin ≤ 450 mg + duloxetine ≤ 120 mg n = 41 Anticonvulsant + SNRI Forced titration to maximum tolerated dose or ceiling dose Double‐dummy design
Outcomes	Pain intensity Quality of life Physical function Mood Sleep Withdrawal
Missing data methods	NR
Funding source	Part funded by pharmaceutical: "This work was supported by CIHR (Canadian Institutes ofHealth) Grant CIHR‐MOP‐106489 and a CIHR‐Pfizer R&D Collaborative Research Investigator Program (CIHR Grant MSH‐55041)."
Conflicts of interest	I. Gilron has received support from Adynxx, Taris Biomedical, Astra Zeneca, Pfizer, and Johnson & Johnson and has received grants from the Canadian Institutes of Health Research, Physicians' Services Incorporated Foundation, and Queen's University. L. E. Chaparro received a John J. Bonica Training Fellowship from the International Association for the Study of Pain and also financial support from the Queen's University Department of Anesthesiology and Perioperative Medicine. R. R. Holden has received research funding from the Canadian Institutes of Health Research, the Social Sciences and Humanities Research Council of Canada, the American Foundation for Suicide Prevention, and Queen's University. R. Milev has received financial support and research grants from CIHR, Ontario Brain Institute, Ontario Mental Health Foundation, Lundbeck, Lilly, Sunovion, BMS, Otsuka, Pfizer, Paladin, and Merck. T. Towheed has received financial support from Abbvie and Bristol‐Meyers‐Squibb and research funding from the Canadian Institutes of Health Research. D. D. Shore. and S. Walker received no external financial support.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomised using computer randomisation of the 3 sequences in blocks of 3.
Allocation concealment (selection bias)	Low risk	A trial pharmacist prepared a concealed allocation schedule, and the pharmacist had no further involvement in the trial. Patients were assigned in turn to the next consecutive number, and the corresponding series of study drugs was dispensed.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double‐blind, matched dosing schedule and double dummy design
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Self‐reported outcomes from blinded participants
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No information on missing data methods Attrition Total: 8/41 (19.5%) Placebo: 1/41 (2.4%) Pregabalin ≤ 450 mg: 1/41 (2.4%) Duloxetine ≤ 120 mg: 3/41 (7.32%) Pregabalin ≤ 450 mg + duloxetine ≤ 120 mg: 4/41 (9.76%)
Selective reporting (reporting bias)	Low risk	Everything as reported in prospectively registered protocol
Other bias	High risk	Taper and washout period were combined, only 1 day complete washout. They state that "primary analysis revealed no significant effects of sequence or carryover, but effects of period and treatment were significant".