Kentner 1996.

Methods	RCT Approved by the ethics committee Setting: Germany Funding: unspecified
Participants	74 patients undergoing urological surgery through a lower abdominal incision
Interventions	Treatment group: lumbar (L3‐L4; catheter advanced 3 to 4 cm) epidural analgesia with 4 mL of mepivacaine 2% plus epinephrine as a test dose followed by 10 to 16 mL of 0.5% bupivacaine plus 5 to 8 mL every 90 to 120 minutes intraoperatively, and 0.25% bupivacaine for 6 hours after surgery followed by 0.175% bupivacaine at 8 mL/h thereafter for 36 hours plus IV patient‐controlled analgesia with piritramide (n = 37) Control group: IV patient‐controlled analgesia with priritramide (n = 37)
Outcomes	Time to first faeces: First bowel movement occurred between postoperative days 3 and 5 with no differences noted between the 2 groups Pain on a 6‐degree scale: Participants in the epidural group had lower pain scores during the first 8 hours
Notes	Data not extractable; study authors contacted on 23 June 2015, and informed us that original data were no longer available
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomized", 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	1 participant given epidural analgesia excluded for catheter dislodgement; 1 participant given opioid analgesia excluded for incomplete data
Selective reporting (reporting bias)	Low risk	All results reported
Other bias	Unclear risk	Groups well balanced Not in intention‐to‐treat