Carette 1995.

Methods	Single centre, R, DB, PC, cross‐over study. 2 x 8‐week treatment periods with no washout. Medication taken as single dose, 1 hour before bedtime Pain, fibromyalgia, sleep, and fatigue assessed at baseline and end of each treatment period
Participants	Inclusion: fibromyalgia (ACR), age ≥ 18 years, baseline pain and/or global assessment of fibromyalgia ≥ 4/10 Excluded: evidence of neurologic, muscular, infectious, endocrine, osseous, or other rheumatological diseases, history of glaucoma, urinary retention, cardiovascular disease, sleep apnoea N = 22, mean age 44 years, M 1/F 21 Mean (SD) duration of fibromyalgia 83 (± 75) months, mean baseline pain 7/10
Interventions	Amitriptyline 25 mg/d (reduced to 10 mg/day if not tolerated), n = 22 Placebo, n = 20 Washout before start of study: 2 weeks for NSAIDs and hypnotics, minimum 4 weeks for antidepressants Paracetamol permitted throughout study
Outcomes	Responder (at least 4/6 from ≥ 50% improvement in pain, sleep, fatigue, patient global assessment, physician global assessment, and increase of 1 kg in total myalgic score) Mean pain intensity Withdrawals
Notes	Oxford Quality Score: R2, DB2, W1. Total = 5/5
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"generated using a table of random numbers"
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"identically appearing placebo tablet"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"identically appearing placebo tablet"
Incomplete outcome data (attrition bias) All outcomes	Low risk	All participants accounted for in responder analysis. Unclear how missing data were handled for mean data
Size	High risk	Fewer than 50 participants/treatment arm