Outcome measurement and follow-up
nausea or vomiting, nausea and/or vomiting, pain
The primary outcome was the occurrence of nausea and/or vomiting within 2 h after randomization [The primary outcome was assessed by independent health care providers who were blinded to the treatment assignments. The outcome assessors evaluated the presence/absence of nausea or vomiting symptom, the severity, the need for rescue therapy or anti-emetic agent, and the pain NRS every 30 min until patient disposition or 2 h after randomization, which ever were reached first.