Arnold 2010.

Methods	Phase IV randomised, double‐blind (subject, caregiver, investigator, outcomes assessor), placebo‐controlled, parallel assignment safety and efficacy study of duloxetine in fibromyalgia
Participants	Men or women Aged 18 and older who meet criteria for fibromyalgia as defined by the American College of Rheumatology With a score of at least 4 on the average pain item of the Brief Pain Inventory (BPI) (modified short form) at visits 1 and 2 All females must test negative for pregnancy at the time of enrolment A degree of understanding such that the potential participant can provide informed consent, complete protocol required assessments and communicate intelligibly with the investigator and study coordinator
Interventions	Duloxetine 60 to 120 mg daily for 24 weeks
Outcomes	Time frame for all outcome measures 24 weeks Primary outcome Patient Global Impression of Improvement (PGI‐I) Secondary outcomes BPI Multidimensional Fatigue Inventory Beck Depression Inventory‐II (BDI II) Clinical Global Impressions of Severity (CGI‐S) Beck Anxiety Inventory SF‐36 (Short Form Health Survey) Massachusetts General Hospital Cognitive and Physical Functioning Questionnaire Anxious Likert Scale Sleep Likert Scale Pain Likert Scale Stiffness Likert Scale Mood Likert Scale Columbia Suicide Severity Rating Scale
Notes	Completed and published
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomly assigned 1:1 in a double‐blind fashion to duloxetine 60 mg once daily or placebo by a computer‐generated random sequence using an IVRS
Allocation concealment (selection bias)	Low risk	"Double blind". "Variable transition to active treatment strategy…thereby blinding the onset of active treatment to reduce the patient's expectation of experiencing side effects"
Blinding (performance bias and detection bias) All outcomes	Unclear risk	No comment on formulation of drug or placebo but almost certainly double blinded both in up and down titration. However, significantly more participants on duloxetine withdrew with adverse effects
Incomplete outcome data (attrition bias) All outcomes	Low risk	Accounted for as much as possible. High dropout rate (> 30%). Employs ITT ‐ use of a "restricted maximum likelihood‐based [mixed effects model repeated measures approach] analysis accounts for bias caused by non‐random missing data due to early discontinuation because of adverse events or lack of efficacy better than LOCF"
Selective reporting (reporting bias)	Low risk	"Patient Global Impression ‐ severity (PGI‐S) only assessed at baseline". Otherwise, paper reports all results
Other bias	Unclear risk	Lilly trial. 93.2% female participants, similar to all fibromyalgia studies