Sallan 1975a.

Study characteristics
Methods	Randomised, double‐blind, 2‐period cross‐over study
Participants	22 people (10 men/12 women) aged 18‐76 years (median = 29.5 years) Tumour types: variety of neoplasms Chemotherapy regimen: adriamycin, 5‐azacytidine, nitrogen mustard, imidazole carboxamide, procarbazine, high‐dose cyclophosphamide or high‐dose methotrexate or combinations. No information on doses reported Chemotherapy emetogenicity: unable to classify
Interventions	Dronabinol 15 mg, later changed to 10 mg/m2, every 4 hours x 3 doses orally, n = 33 Placebo, n = 33
Outcomes	Episodes of nausea and vomiting on day after treatment, withdrawal due to adverse effects, episodes of feeling high, somnolence, paranoia, hallucination
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not reported
Allocation concealment (selection bias)	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	High risk	20/33 (61%) participants received THC, 22/33 (67%) participants received placebo
Selective reporting (reporting bias)	Low risk	Data reported for primary outcome
Other bias	Unclear risk	Assumed washout period sufficient. Unclear if paired analysis was performed. Unclear if groups were balanced at baseline
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"Identical gelatin capsules used"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinding assumed as study reported as "double‐blind" and "identical gelatin capsules used"