Chung 2000.

Methods	Randomised double‐blind placebo‐controlled cross‐over trial for 2 successive 6‐week treatment periods with 1‐week washout period.
Participants	6 children with CF randomised, 1 excluded because of positive H. pylori. Data from 5 children aged 5 ‐ 12 years.
Interventions	2 groups: 1. placebo; 2. omeprazole 10 mg/day or 20 mg/day depending on weight.
Outcomes	Faecal fat, CBC, SMAC, prealbumin, height, weight, malabsorption symptom checklist, genotype analysis, H. pylori status.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Described as randomised, but no details of method given.
Allocation concealment (selection bias)	Unclear risk	Not discussed.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Described as double‐blind in text but no further details given.
Incomplete outcome data (attrition bias) All outcomes	Low risk	1 child excluded because of positive H. pylori, data available from 5 remaining participants.