Salo 2010.

Methods	Study design: parallel RCT Power calculation: provided, justified, although highly optimistic Intention‐to‐treat analysis: no, 8 excluded
Participants	Inclusion criteria Setting: 7 centres, (4 university paediatric departments, 3 centralised hospitals) Country: Finland Children referred to paediatric departments of 4 university hospitals or 3 centra hospitals for verified UTI in previous 2 months, 2001‐2008 Number: 263 randomised; 255 analysed Exclusion criteria Children with grade III‐V VUR or severe genitourethral malformations
Interventions	Cranberry juice 5mL/kg up to 300mL 1‐2 doses daily for 6 months or Placebo juice same volume and dose per day as cranberry
Outcomes	Repeat UTI
Notes	Details are from the trial registration, Salo abstract and journal article
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Block size 4, externally managed
Allocation concealment (selection bias)	Low risk	Sealed envelopes
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Double blind, states clinician and parents blind
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not specifically stated
Incomplete outcome data (attrition bias) All outcomes	Low risk	Few missing data Losses to follow‐up/withdrawals: 27 drop outs (16 in cranberry arm, 11 in placebo group) Exclusions post randomisation: 8
Selective reporting (reporting bias)	Low risk	Most appropriate outcome used
Other bias	Low risk	Well reported study Source of funding: Paivikki and Sakari Sohlberg Foundation, Foundation for Paediatric research, Paulo Foundation, Ocena Spray