Allen 2017.

Study characteristics
Methods	Design: parallel Duration: 15 weeks (intended to be 27 weeks but terminated early) Assessment: baseline, study termination (15 weeks) Country: USA
Participants	Pain condition: fibromyalgia Population: adults with fibromyalgia Inclusion criteria fibromyalgia diagnosis according to the ACR 1990 diagnostic criteria, including widespread pain for > 3 months with at least 11 of 18 defined tender points on examination at screening and baseline. Average pain score of ≥ 4 on the 0‐10 NRS Exclusion criteria Previous treatment with desvenlafaxine, a history of intolerance of venlafaxine, or a history of drug allergies, pregnancy or breastfeeding, history of seizure disorder, neoplastic disorder within 5 years, myocardial infarction within 6months, stroke or transient ischaemic attack within 3 years, narrow‐angle glaucoma, or clinically important abnormalities on screening The presence of a clinically important medical disease, presence or history of psychotic, bipolar, or major depressive disorder, alcohol or drug abuse/dependence, or evidence of significant risk of suicide or self ‐harm Total participants randomised: 697 Age in years (mean, SD): NR Gender: NR Pain duration: NR
Interventions	Desvenlafaxine 50 mg 136 participants fixed dose of 50 mg/day Desvenlafaxine 100 mg 139 participants fixed dose of 100 mg/day Desvenlafaxine 200 mg 142 participants fixed dose of 200 mg/day Desvenlafaxine 400 mg 149 participants fixed dose of 400 mg/day Placebo 130 participants
Outcomes	Pain intensity 50% pain reduction PGIC AE SAE Withdrawal
Missing data methods	LOCF
Funding source	Pharmaceutical: Wyeth Research, now incorportated into Pfizer
Conflicts of interest	Rob Allen, MD, is a former Pfizer employee currently working as an independent consultant. Suna Barlas, PhD, is a Pfizer employee. Uma Sharma, PhD, is a former Pfizer employee and currently works at MMS Holdings Inc.
Notes	Study terminated early (at 15 weeks instead of 27 weeks) due to interim efficacy analysis not meeting the preplanned efficacy criteria
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not enough information ‐ just says 'randomly assigned'
Allocation concealment (selection bias)	Unclear risk	No information given
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	No information on matching appearance or dosing schedules of antidepressants and placebo
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Self‐reported outcomes by participants, but blinding information unclear
Incomplete outcome data (attrition bias) All outcomes	High risk	Study terminated, so missing data from all time points past 15 weeks. LOCF. Very high attrition across all arms before study termination. Attrition: Total: 445/697 (63.8%) Placebo: 84/130 (67.7%) Desvenlafaxine 50 mg: 87/136 (66.0%) Desvenlafaxine 100 mg: 81/140 (62.0%) Desvenlafaxine 200 mg: 100/142 (76.0%) Desvenlafaxine 400 mg: 93/149 (67.0%)
Selective reporting (reporting bias)	Low risk	Protocol stated the interim analyses
Other bias	Low risk	Study terminated early, but this was due to interim efficacy analyses not meeting the prespecified criteria.