Kashikar‐Zuck 2012

Methods	RCT. 2 arms. Assessed pre‐treatment, post‐treatment, 6‐month follow‐up
Participants	End of treatment n = 106; follow‐up 6 months n = 100 Start of treatment n = 114 Sex: 105 F, 9 M Mean age = 15.0 (1.8) Source = paediatric rheumatology centres in Midwestern USA Diagnosis = fibromyalgia syndrome Mean years of pain = 2 years, 10 months (2 years, 6 months)
Interventions	"Cognitive behavioural therapy" "Fibromyalgia education"
Outcomes	Primary pain outcome: pain severity VAS (averaged over 7 days) Primary disability outcome: Functional Disability Scale Primary depression outcome: Children's Depression Inventory Primary anxiety outcome: Pain Coping Questionnaire 1. Pain severity VAS (averaged over 7 days) 2. Functional Disability Scale 3. Children's Depression Inventory 4. Tender point sensitivity 5. Pedatric Quality of Life Inventory 6. Sleep quality VAS (averaged over 7 days) 7. Physician's global assessment VAS
Notes	Updated study 2012 Total quality = 32/35 Treatment quality = 9/9 Design quality = 23/26
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Eligible patients were randomly assigned to 1 of the 2 treatment arms based upon a computer‐generated randomisation list. Randomisation was stratified by site." Comment: probably done
Allocation concealment (selection bias)	Low risk	"When a patient was enrolled, the study therapist contacted the biostatistician to obtain the subject identification number and treatment allocation." Comment: probably done
Blinding of outcome assessment (detection bias) All outcomes	Low risk	"The principal investigator, study physicians, study coordinator, and assessment staff were all blinded to the patients' treatment condition throughout the trial. Patients were asked not to divulge what treatment they were receiving to the study physician." Comment: probably done
Incomplete outcome data (attrition bias) All outcomes	Low risk	Attrition is described; no significant differences between completers and non‐completers were reported
Selective reporting (reporting bias)	Low risk	Data were fully reported