Han 2001.

Methods	Clinical trial in China.
Participants	Inclusion criteria: newborns age 1 to 12 days. Most infants with severe illness. Term and preterm. Exclusion criteria: if swallowed maternal blood, bleeding outside gastrointestinal tract, abnormal clotting, constipation, necrotising enterocolitis.
Interventions	Intervention (n = 43): cimetidine 5 mg/kg per day for 5 days. Control (n = 40): no cimetidine.
Outcomes	Acute gastric mucosal lesion (diagnosed by vomiting of bright red or coffee‐like liquid or faecal occult blood positive or tarry stool).
Notes	Authors did not believe there were any adverse reactions attributable to the intervention.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Reported 'random'.
Allocation concealment (selection bias)	Unclear risk	Method not reported.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not reported.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported.
Incomplete outcome data (attrition bias) All outcomes	Low risk	None reported.
Selective reporting (reporting bias)	Unclear risk	No protocol available.
Other bias	Low risk	Similar baseline characteristics between groups.