Durie 1980.

Methods	Randomised cross‐over trial of 4 periods of 7 days treatment.
Participants	21 people with CF, age range 10 ‐ 17 years. 6 withdrawals: 2 voluntarily after 3 days; 3 on evidence of poor drug and diet compliance and inadequate stool collection; and 1 with a possible complication with cimetidine.
Interventions	4 groups: 1. pancreatic supplement (Pancrelipase, 27 capsules per day); 2. pancreatic supplement plus cimetidine (20 mg/kg body weight/24h); 3. pancreatic supplement plus sodium bicarbonate (15g/m2/24h); 4. pancreatic supplement plus cimetidine (20 mg/kg body weight/24h) and sodium bicarbonate (15g/m2/24h).
Outcomes	Faecal fat (gm/24 h and %)
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	Level of blinding not discussed.
Incomplete outcome data (attrition bias) All outcomes	Low risk	6 withdrawals: 2 voluntarily after 3 days; 3 on evidence of poor drug and diet compliance and inadequate stool collection; and 1 with a possible complication with cimetidine.