Ho 1996.

Methods	Parallel‐group randomized trial, conducted in Taiwan. Study dates not reported.
Participants	60 women receiving epidural morphine for post‐Caesarean section pain relief. Excluded: previous carpal tunnel syndrome, or those who had experienced nausea or vomiting within 24 h before Caesarean section.
Interventions	Group 1: acupressure wristbands on P6 acupoint of both wrists before administration of spinal anaesthesia. Worn for 48 hours (n = 30). Group 2: sham acupressure wristbands on both wrists but plastic button was blunted in order not to exert pressure on P6 acupoint. Worn for 48 hours (n = 30).
Outcomes	Nausea (0 ‐ 48 h), vomiting (0 ‐ 48 h), risk of rescue antiemetic drug, side effects of acupressure wristbands.
Notes	Rescue antiemetic was metoclopramide. No side effects were noted. 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	"Randomization was conducted by computer..".
Allocation concealment (selection bias)	Unclear risk	"... With each code sealed in an envelope to be opened upon the parturient's arrival in the operating room". Comment: not sure if envelopes were sequentially numbered and opaque.
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	"An independent anaesthesiologist blinded to the parturient groups followed up all parturients".
Incomplete outcome data (attrition bias) All outcomes	Low risk	"All parturients completed the trial and tolerated the bands well".
Selective reporting (reporting bias)	Low risk	All expected outcomes reported.
Other bias	Low risk	Baseline characteristics were comparable. "There were no statistically significant difference with respect to age, weight, height, duration of operation, intraoperative blood loss, duration of pain relief, total epidural morphine dosage, percentage of parturients requiring additional analgesics and total time spent wearing bands between the two groups".