Nicassio 1997.

Methods	Study setting: North America (USA). Single centre university psychiatry department, outpatient based, referral by community, private or university rheumatology clinics, FMS support groups Study design: Parallel Duration therapy: 10 weeks Follow‐up: 6 months Analysis: MANOVA between groups at pre‐treatment on clinical criteria and intervening variables, MANOVA between treatment conditions and across time (pre‐, post‐treatment, follow‐up periods) on clinical criteria and intervening variables (helplessness, active coping, passive coping, quality of social support), change score correlations to see whether helplessness and passive coping mediate changes, regression analysis (predictors: helplessness, passive coping)
Participants	Patients: Total group: 89% female, 86% white, mean age 53.1 years; CBT group 36 patients, control group 35 patients; duration of symptoms not reported Inclusion: Diagnosis of FM confirmed by rheumatologist according to ACR 1990 criteria, stabilization on medication for at least 2 months prior to the study, support person who would be willing to participate in the study Exclusion: Concomitant rheumatologic conditions, cardiovascular disease, central nervous system disorders, psychosis, bipolar illness
Interventions	Treatment Group: CBT, group: education, relaxation, activity pacing, pain coping, involvement of support person reinforcing adherence to protocol (1x1.5h/week), total: 15h Control Group: Attention control, group: lectures, group discussion, support (1.5h/week), total: 15h Co‐medication allowed: Yes, not controlled for Other Co‐therapies: Not reported
Outcomes	Primary Outcomes Self reported pain: Pain index composed by (a) pain scale of the FIQ, b) number of discrete body areas endorsed as painful form a human figure drawing, c) pain rating index of MPQ, d) flare index: frequency times the squared average intensity of pain flares over previous month; no minimum and maximum scores available Self reported negative mood: Center for Epidemiological Studies‐Depression Scale (CES‐D) 0‐60 Self reported disability: Quality of well‐being 1‐0 Acceptability: Total dropout rate Secondary Outcomes Self reported self efficacy pain: Pain Management Inventory Subscale active coping Self reported fatigue: Not assessed Self reported sleep problems: Not assessed Self reported disease‐specific health‐related quality of life: Not assessed
Notes	1. Reasons for dropout: not reported 2. Attendance rates: Not reported 3: Responder analysis: None 4. Funding sources and declaration of interest of the primary researchers: Multipurpose Arthritis and Musculoskeletal Diseases Center Grant AR40770 and grant from the General Clinical Research Centers M01RR00827 of the MCRR from the US National Institute of Health
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Subjects were randomly assigned with the aid of a random number table from within blocks to the interventions
Allocation concealment (selection bias)	Unclear risk	No detailed information
Incomplete outcome data (attrition bias) All outcomes	High risk	No intention‐to‐treat analysis
Selective reporting (reporting bias)	Low risk	All outcomes reported
Blinding of outcome assessor	Unclear risk	No detailed information