Marshall 1989.

Methods	RCT Cross‐over
Participants	Any child with a paediatric malignancy on any chemotherapy protocol including BMT conditioning in 6 participants, who had a second course planned. Median age 7 years (4 to 15 years), with 17/26 male
Interventions	Chlorpromazine 0.825 mg/kg QDS IV for 4 doses Cocktail. Metoclopramide (IV) 2 mg/kg/dose 0, 2, 6, 12 hours. Dexamethasone (IV) 0.7 mg/kg 0 hours. Benzatropine (IV) 0.02 mg/kg/dose 0, 6 hours. Lorazepam (PO) 0.05 mg/kg/dose, 1 hour and 12 hours
Outcomes	Recorded number and duration of vomiting using ?structured interview ‐ unclear
Notes	—
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not stated
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding (performance bias and detection bias) Acute nausea	Unclear risk	Not reported
Blinding (performance bias and detection bias) Acute vomiting	Unclear risk	"Double blinded" but unclear how effective the placebos would be Blinding of care provider: unclear Blinding of participant: unclear Blinding of outcome assessors: unclear
Blinding (performance bias and detection bias) Other outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	2/26 did not complete the cross‐over
Selective reporting (reporting bias)	Low risk	—
Other bias	Unclear risk	6/26 on conditioning regimens given after 24 hours ‐ could there be a carry‐over effect?