Ravi 2010.

Methods	Parallel‐group randomized trial, conducted in India. Study dates not reported.
Participants	50 people aged 4 ‐ 60 years with ASA physical status I or II undergoing surgery (general, laparoscopic, ENT, paediatric, orthopaedic, obstetric, gynaecological) under general anaesthesia. Exclusion criteria: people with cardiovascular disease, central nervous system problems, previous history of PONV and motion sickness, and smokers.
Interventions	Group 1: P6 acupoint injection with 50% 0.2 ml dextrose after induction of anaesthesia (n = 25). Group 2: Ondansetron (50 µg/kg) at end of surgery (n = 25).
Outcomes	Nausea (0 ‐6 h), vomiting (0 ‐6 h), rescue antiemetic (ondansetron 4 mg)
Notes	Subgroup analysis for adults and children not done as overall population was mixed in age range (4 ‐ 60 years). No details about funding source or any declarations of interest among authors.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated random numbers table.
Allocation concealment (selection bias)	Unclear risk	Insufficient details given.
Blinding of patients (performance bias) All outcomes	Low risk	"Both patients and doctors were unaware of the group allocation."
Blinding of healthcare providers (performance bias) All outcomes	Low risk	"Both patients and doctors were unaware of the group allocation."
Blinding of outcome assessor (detection bias) All outcomes	Low risk	"An anaesthetist blinded for the study assessed the presence of nausea and vomiting."
Incomplete outcome data (attrition bias) All outcomes	Low risk	No missing data reported for the 50 participants analysed.
Selective reporting (reporting bias)	High risk	Incidence of rescue ondansetron 4 mg for intolerable PONV in recovery room and postoperative ward not reported.
Other bias	Low risk	Age, sex ratio, weight of participants and duration of surgery were similar between groups.