Gralla 1984.

Study characteristics
Methods	Randomised, double‐blinded parallel group trial
Participants	31 people (23 men/ 5 women). THC n = 15 (13 men/2 women), aged 39‐72 years (median = 58 years); metoclopramide n = 16 (11 men/5 women), aged 45‐70 years (median = 58 years) Tumour types: bronchogenic carcinoma (12 people), oesophageal carcinoma (2 people), head and neck carcinoma head and neck carcinoma (1 person) Chemotherapy regimens: all receiving first course of cisplatin 120 mg/m2 IV Chemotherapy emetogenicity: high
Interventions	Dronabinol 10 mg/m2 1.5 hours prior to chemotherapy, then at 1.5, 4.5, 7.5 and 10.5 hours after chemotherapy orally, n = 15 Metoclopramide, 2 mg/kg 30 minutes prior to chemotherapy, then 1.5, 3.5, 5.5 and 8.5 hours after chemotherapy IV, n = 16
Outcomes	Episodes of nausea and vomiting during 24 hours, sedation, dizziness, orthostatic hypotension, feeling high
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Paired design in which one patient in every pair was randomly assigned to each treatment"
Allocation concealment (selection bias)	Low risk	"Identical vials and capsules used"
Incomplete outcome data (attrition bias) All outcomes	Low risk	15/15 (100%) participants received THC, 15/16 (94%) participants received metoclopramide
Selective reporting (reporting bias)	Low risk	Data reported for primary outcome
Other bias	Unclear risk	Unclear if groups were balanced at baseline
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"Identical vials and capsules used"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinding assumed as study reported as "double‐blind"