Arnold 2012.

Methods	Randomised, double‐blind, placebo‐controlled, parallel group study of duloxetine in fibromyalgia
Participants	Women and men > 18 years of age who met the American College of Rheumatology 1990 criteria for primary fibromyalgia and had a score of > 4 on the average pain severity item of the Brief Pain Inventory (BPI)‐Modified Short Form. Patients with or without major depressive disorder or generalised anxiety disorder, as defined by the DSM‐IV and confirmed by the MINI were included.
Interventions	Duloxetine 30 mg capsules or placebo for 12 weeks
Outcomes	Primary outcome 24 hour pain severity on the BPI‐Modified Short Form Secondary outcomes Patient global impression of improvement Fibromyalgia Impact Questionnaire response rate (30% or 50% reduction in BPI average pain severity) BPI pain severity items (pain right now, worst pain, least pain) and BPI interference score Clinical Global Impression ‐ Improvement scale (CGI‐I) for depression Beck Depression Inventory II Beck Anxiety Inventory Short Form Health Survey (SF‐36) adverse events (treatment emergent, serious, vital signs and analytes, Columbia Suicide Severity Scale
Notes	Lilly study. No other bias identified
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomisation by a computer‐generated random sequence using an interactive voice response system (IVRS)
Allocation concealment (selection bias)	Unclear risk	Unclear
Blinding (performance bias and detection bias) All outcomes	Low risk	The duloxetine and placebo capsules were identical in appearance to maintain the blinding. Participants and investigators were kept blinded to the rescue criteria and dose increase; site personnel entered the major depressive disorder status at baseline and the CGI‐I for Depression scores through IVRS at every visit
Incomplete outcome data (attrition bias) All outcomes	Low risk	Only 2 dropouts, both from duloxetine group and likely to have been of minimal significance
Selective reporting (reporting bias)	Low risk	Most outcomes presented except individual BPI severity items (worst pain, least pain, pain right now). However, no other outcomes with significant effect in completely negative trial
Other bias	Low risk	Lilly study. No other bias identified