Pawar 2008.

Study characteristics
Methods	Study design: randomized controlled trial Study grouping: 3 groups, monoprophylaxis and combination prophylaxis
Participants	Baseline characteristics Ondansetron + dexamethasone (group 1) Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): NA Received treatment (n): NA Analysed (n): NA Age (mean ± SD, median (IQR), median (range)): 35.65 Weight (mean ± SD, median (IQR), median (range)): 58.75 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA/NA/0/0 Gender (female in %): 100 Non‐smoker (%): NA History of PONV/motion sickness (%): NA Type of general anaesthesia: inhalational anaesthesia (N₂O) Duration of anaesthesia or surgery (in min; as mean or median): less than 30 minutes Use of perioperative opioids (if yes, which?): NA Type of surgery: gynaecological laparoscopic intervention Ondansetron (group 2) Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): NA Received treatment (n): NA Analysed (n): NA Age (mean ± SD, median (IQR), median (range)): 32.62 Weight (mean ± SD, median (IQR), median (range)): 56.65 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA/NA/0/0 Gender (female in %): 100 Non‐smoker (%): NA History of PONV/motion sickness (%): NA Type of general anaesthesia: inhalational anaesthesia (N₂O) Duration of anaesthesia or surgery (in min; as mean or median): less than 30 minutes Use of perioperative opioids (if yes, which?): NA Type of surgery: gynaecological laparoscopic intervention Dexamethasone (group 3) Assessed for eligibility (n): ‐ Enrolled (n): ‐ Randomized (n): NA Received treatment (n): NA Analysed (n): NA Age (mean ± SD, median (IQR), median (range)): 33.82 Weight (mean ± SD, median (IQR), median (range)): 57.65 BMI (mean ± SD, median (IQR), median (range)): NA ASA I/II/III/IV (n): NA/NA/0/0 Gender (female in %): 100 Non‐smoker (%): NA History of PONV/motion sickness (%): NA Type of general anaesthesia: inhalational anaesthesia (N₂O) Duration of anaesthesia or surgery (in min; as mean or median): less than 30 minutes Use of perioperative opioids (if yes, which?): NA Type of surgery: gynaecological laparoscopic intervention Included criteria: 18 to 65 years of age, ASA I or II, undergoing gynaecological laparoscopic intervention under general anaesthesia Excluded criteria: ASA III or above, previous history of drug reaction to any of the drugs used in this study, history of PONV, history of motion sickness, received antiemetics in the previous 24 hours, evidence of respiratory infection Pretreatment: baseline characteristics (age, ASA, weight): no. Potential effect modifiers (gender, duration of anaesthesia): no; (history of PONV/motion sickness, non‐smoker, perioperative opioids): unclear
Interventions	Intervention characteristics Ondansetron + dexamethasone (group 1) Dose: ondansetron 4 mg, dexamethasone 8 mg Time point of administration: 5 minutes before induction of anaesthesia Route of administration: IV Rescue antiemetics (if yes, which?): granisetron 1 mg Ondansetron (group 2) Dose: 4 mg Time point of administration: 5 minutes before induction of anaesthesia Route of administration: IV Rescue antiemetics (if yes, which?): granisetron 1 mg Dexamethasone (group 3) Dose: 8 mg Time point of administration: 5 minutes before induction of anaesthesia Route of administration: IV Rescue antiemetics (if yes, which?): granisetron 1 mg
Outcomes	Adverse events (general notes in the publication, 24 hours' observation) Outcome type: general notes on side effects
Identification	Sponsorship source: NA Country: India Setting: NA, single‐centre Author's name: Aarti Nandkumar Pawar Institution: Department of Anaesthesia, KEM Hospital Email: NA Address: Acharya Donde Marg, Parel, Mumbai, Maharashtra 400012, India Duration of study: NA Language: English Study's primary outcome: NA Trial registry number: NA
Notes	None
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "prospective, randomized study was conducted..." Judgement comment: no further information on randomization method provided
Allocation concealment (selection bias)	Unclear risk	Judgement comment: no statement
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Judgement comment: no statement
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "...of nausea episodes of vomiting. These observations were recorded by independent recovery room personnel who did not know which anti‐emetic each patient had received. Every complaint of nausea..."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Judgement comment: no Information on number of patients who were randomized and analysed
Selective reporting (reporting bias)	Unclear risk	Judgement comment: no reference to a study protocol or trial registry number reported
Other bias	Unclear risk	Quote: "...be 58.75, 56.65, 57.65 respectively. Therefore the age and the weight distribution was comparable in the 3 groups. Average number of patients with..." Judgement comment: baseline characteristics (age, ASA, weight): no. Potential effect modifiers (gender, duration of anaesthesia): no; (history of PONV/motion sickness, non‐smoker, perioperative opioids): unclear