Cai 2007.

Methods	RCT Setting: China Funding: departmental
Participants	62 ASA 1 to 2 patients, aged 33 to ˜60 years, weighing 42 to ˜56 kg, scheduled for elective gastrectomy Exclusion criteria were abnormal heart, lung, liver, kidney and coagulation function and history of recent use of hormone or non‐steroidal anti‐inflammatory drugs
Interventions	Treatment groups: thoracic epidural analgesia (T7‐T8; catheter advanced 3 to 4 cm passed the needle tip, test dose 3 mL of 1% lidocaine) with ropivacaine 0.25% (for sensory level to T4) and morphine 2 mg (before surgical incision), combined with postoperative epidural analgesia with ropivacaine 0.15% and morphine 1.5 mcg/mL at 2 mL/h for 72 hours (n = 22) or ropivacaine 0.25% 10 mL and morphine 2 mg (before surgical incision, postoperative epidural analgesia with ropivacaine 0.15% and morphine 1.5 mcg/mL at 2 mL/h for 72 hours (n = 22) Control group: postoperative intravenous analgesia with fentanyl 0.1 mg IV at the end of surgery, followed by continuous intravenous fentanyl 0.25 mcg//mL and droperidol 0.05 mg/mL at a rate of 2 mL/h for 72 hours (n = 22) General anaesthesia with propofol, fentanyl isoflurane and vecuronium for all participants
Outcomes	Pain scores at rest and on coughing (taken as on movement) at 8, 12, 24, 48 and 72 hours after surgery
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomly divided", no details
Allocation concealment (selection bias)	Unclear risk	Not mentioned
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not mentioned
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not mentioned
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up mentioned
Selective reporting (reporting bias)	Low risk	All results reported
Other bias	Low risk	Groups well balanced