Robins 2005.

Methods	RCT with usual care control Follow‐up: postintervention (3 months), 6 months' and 12 months' follow‐up
Participants	Location: USA Setting: recruited from paediatric gastroenterology clinics Sample size: 86 children (46 intervention, 40 control) Sex: 30 boys, 39 girls (data reported for completers only) Dropouts/withdrawals: 11 control Diagnosis: RAP diagnosed using Apley criteria (Apley 1958) Mean age: intervention: 10.8 (SD 2.5; range not reported) years; control: 11.9 (SD 2.3; range not reported) years. Overall range for both groups: 6 to 16 years
Interventions	Intervention: cognitive behavioural therapy, for child and parent (non‐group format), 40 minutes x 5, every 2 weeks, as well as usual medical care Control: usual medical care (usual individualised care including visits with physicians and advice on diet)
Outcomes	Pain (Abdominal Pain Index; Walker 1997): child and parent Functional disability due to pain (Functional Disability Inventory; Walker 1991): child
Notes	Study dates: August 1998 to April 2000 Funding: grant from the Nemours Research Programs Declarations of Interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: coin flip status, with a witness, but procedure unclear
Allocation concealment (selection bias)	Unclear risk	Comment: no details provided of how coin flip was managed, or whether done in advance
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: only clinicians delivering usual medical care were blinded
Blinding of outcome assessment (detection bias) All outcomes	High risk	Comment: self report outcomes and participants aware of intervention
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Comment: clear numbers at follow‐up not reported
Selective reporting (reporting bias)	Low risk	Comment: all outcomes reported
Other bias	Unclear risk	Comment: issues relate to differences at baseline, sufficient numbers not recruited, larger loss to follow‐up than expected, and merged results