Kim 2004.

Methods	Parallel‐group randomized trial conducted in Korea.
Participants	66 women, ASA physical status I or II, undergoing sevoflurane general anaesthesia for minor breast surgery. Exclusion criteria were women with respiratory, circulatory or neurological disease, liver or kidney dysfunction, nausea or vomiting in the 24 h before surgery, receiving antiemetics, pregnant women and excessively obesity.
Interventions	Group 1: Transcutaneous electrical stimulation (ReliefBand) on P6 acupoint 10 min before surgery and left in place for 24 h. Bilateral or unilateral simulation not reported (n = 33). Group 2: Sham transcutaneous electrical stimulation (inactivated ReliefBand) on P6 acupoint 10 min before surgery and left in place for 24 h. Bilateral or unilateral sham simulation not reported (n = 33).
Outcomes	Nausea (0 ‐ 24 h), vomiting (0 ‐ 24 h), risk of rescue antiemetic drug (ondansetron 4 mg IV).
Notes	Descriptive data taken from information in Kim 2012.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient details.
Allocation concealment (selection bias)	Unclear risk	Insufficient details.
Blinding of patients (performance bias) All outcomes	Low risk	Inactivated device that looks similar to the real device.
Blinding of healthcare providers (performance bias) All outcomes	Unclear risk	Insufficient details.
Blinding of outcome assessor (detection bias) All outcomes	Low risk	Unaware of allocated treatment at both baseline and postoperative evaluations.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No reported dropouts or withdrawals.
Selective reporting (reporting bias)	Low risk	All expected measured outcomes were reported.
Other bias	Low risk	Baseline characteristics were comparable.