Laha 2013.

Study characteristics
Methods	Study design: randomized controlled trial Study grouping: 2 groups, monoprophylaxis
Participants	Baseline characteristics Palonosetron Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): NA Received treatment (n): NA Analysed (n): 49 Age (mean ± SD, median (IQR), median (range)): 43.3 ± 14.25 Weight (mean ± SD, median (IQR), median (range)): 57.1 ± 9.61 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA Gender (female in %): 10.20 Non‐smoker (%): NA History of PONV/motion sickness (%): NA Type of general anaesthesia: inhalational anaesthesia (sevoflurane, N₂O) Duration of anaesthesia or surgery (in min; as mean or median): 90 Use of perioperative opioids (if yes, which?): 2 µg/kg fentanyl intraoperative Type of surgery: laparoscopic cholecystectomy Ondansetron Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): NA Received treatment (n): NA Analysed (n): 49 Age (mean ± SD, median (IQR), median (range)): 44.9 ± 13.36 Weight (mean ± SD, median (IQR), median (range)): 60.4 ± 9.99 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA Gender (female in %): 24.49 Non‐smoker (%): NA History of PONV/motion sickness (%): NA Type of general anaesthesia: inhalational anaesthesia (sevoflurane, N₂O) Duration of anaesthesia or surgery (in min; as mean or median): 79.2 ± 24.3 Use of perioperative opioids (if yes, which?): 2 µg/kg fentanyl intraoperative Type of surgery: laparoscopic cholecystectomy Included criteria: over 18 years age, either sex, undergoing elective laparoscopic cholecystectomy at a tertiary care hospital Excluded criteria: pregnancy; body weight > 30% of ideal body weight; distinct spells of nausea, vomiting, or retching within 24 hours before surgery; use of corticosteroids, psychoactive drugs, or any other medication with known emetic or antiemetic effect within 24 hours before surgery; significant disease of major organs like liver, kidneys, heart, lungs, and bone marrow; known hypersensitivity to study medication; history of alcohol or substance abuse; participation in any other clinical trial within the last month Pretreatment: baseline characteristics (age, weight): no; (ASA): unclear. Potential effect modifiers (gender, duration of anaesthesia, perioperative opioids): no; (history of PONV/motion sickness, non‐smoker): unclear
Interventions	Intervention characteristics Palonosetron Dose: 75 μg Time point of administration: 1 minute before induction of anaesthesia Route of administration: IV Rescue antiemetics (if yes, which?): metoclopramide 10 mg PO Ondansetron Dose: 4 mg Time point of administration: 1 minute before induction of anaesthesia Route of administration: IV Rescue antiemetics (if yes, which?): metoclopramide 10 mg PO
Outcomes	Complete response (no PONV) in 24 hours Outcome type: dichotomous outcome Subjects with any AE (0 to 24 hours) Outcome type: dichotomous outcome Constipation (time point unknown) Outcome type: dichotomous outcome Adverse events (general notes in the publication, 24 hours' observation) Outcome type: general notes on side effects
Identification	Sponsorship source: nil Country: India Setting: inpatient, single‐centre Author's name: Avijit Hazra Institution: NA Email: ni.oc.oohay@snafwolb Address: NA Language: English Duration of study: NA Trial registry number: NA Study's primary outcome: PONV
Notes	None
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "simple randomization was done in 1:1 ratio on the basis of a computer generated random number list"
Allocation concealment (selection bias)	Low risk	Quote: "generated random number list and allocation was concealed till the point of drug administration using serially numbered opaque sealed envelopes. The medication was administered..."
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "single blind manner, taking care to ensure that the patient was not aware of the exact identity of the antiemetic drug" Judgement comment: personnel was aware of the study drug
Blinding of outcome assessment (detection bias) All outcomes	High risk	Judgement comment: personnel was aware of the study drug
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "the study was completed by all recruited subjects"
Selective reporting (reporting bias)	Unclear risk	Judgement comment: no reference to a study protocol or trial registry number reported
Other bias	Unclear risk	Judgement comment: baseline characteristics (age, weight): no; (ASA): unclear. Potential effect modifiers (gender, duration of anaesthesia, perioperative opioids): no; (history of PONV/motion sickness, non‐smoker): unclear