Agarwal 2002.

Methods	Parallel‐group randomized trial, conducted in India. Study dates not reported.
Participants	150 adults undergoing laparoscopic cholecystectomy. Exclusion: patient refusal to participate in study, previous history of PONV and motion sickness, impaired renal function with increased urea and creatinine concentrations, diabetes mellitus, obesity, patients receiving antiemetic medication, histamine H₂ receptor antagonist within 72 hours of surgery.
Interventions	Acupressure wristband placed at P6 points on both forearms, applied 30 min before induction of anaesthesia and removed after 6 hours following surgery (plus normal saline 1 mL IV just before induction of anaesthesia) (n = 50). Sham group was the spherical bead of acupressure wristbands placed on posterior surface, applied 30 min before induction of anaesthesia and removed 6 hours after surgery (plus normal saline 1 mL IV just before induction of anaesthesia) (n = 50). Antiemetic group was ondansetron 4 mg IV just before induction of anaesthesia (plus sham treatment outlined above) (n = 50).
Outcomes	Nausea (0 ‐ 24 h), vomiting (0 ‐ 24 h), risk of rescue antiemetic drug.
Notes	Rescue antiemetic was ondansetron 4 mg IV if participant vomited more than once. No side effects or complications noted in any of the groups. Data for outcome (0 ‐ 24 h) obtained by correspondence with author. 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	"Patients were randomised into three groups of 50 each using a table of random numbers..".
Allocation concealment (selection bias)	Unclear risk	Insufficient information.
Blinding of patients (performance bias) All outcomes	Low risk	Authors took adequate steps to make interventions appear similar.
Blinding of healthcare providers (performance bias) All outcomes	Unclear risk	Insufficient information.
Blinding of outcome assessor (detection bias) All outcomes	Low risk	"The incidence of PONV was evaluated by a blinded observer".
Incomplete outcome data (attrition bias) All outcomes	Low risk	No missing data reported for 150 patients randomized.
Selective reporting (reporting bias)	Low risk	All expected outcomes reported.
Other bias	Low risk	Baseline characteristics were comparable: "Patients were comparable in both the groups as regards to age, sex, height, weight and duration of surgery".