Palermo 2016.

Methods	RCT with education control Follow‐up: postintervention (8 to 10 weeks) and 6 months' follow‐up
Participants	Location: USA and Canada Setting: recruited from paediatric pain clinics Sample size: 31 children (17 intervention, 14 control); children with headache not included in analysis Sex: 11 boys, 20 girls Dropouts/withdrawals: none reported Diagnosis: chronic idiopathic abdominal pain Mean age: intervention: 13.7 (SD 1.3; range 11 to 17) years; control 14.5 (SD 2.0; range 11 to 17) years. Data not reported for groups overall.
Interventions	Intervention: Internet‐delivered cognitive behavioural child and parent intervention (non‐group format), 30 minutes/week x 8 for both child and parent (4 hours total for each) Control: Internet‐delivered education child and parent intervention (non‐group format), 30 minutes/week x 8 for both child and parent (4 hours total for each)
Outcomes	Pain intensity (0 to 10 scale) Activity limitations (Child Activity Limitations Interview; Palermo 2004)
Notes	Study dates: September 2011 to April 2014 Funding: grant HD062538 from the National Institutes of Health ‐ Eunice Kennedy Schriver National Institute of Child Health and Human Development Declarations of interest: Authors report no conflicts of interest.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Comment: computerised random number generator
Allocation concealment (selection bias)	Low risk	Comment: computerised random number generator linked automatically to web program
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Comment: unsure what information participants were given with consent; it is therefore difficult to know whether they were truly 'unaware' of allocation as is suggested by author
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: unaware of intervention but self reporting outcome
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: accounted for all participants
Selective reporting (reporting bias)	Low risk	Comment: all variables presented
Other bias	Low risk	Comment: baseline variables similar, well‐reported paper