Ozcan 2004.

Methods	RCT Approved by the ethics committee and informed consent obtained Setting: Turkey Funding: unspecified
Participants	60 ASA 1 to 2 women undergoing abdominal hysterectomy through a Pfannenstiel incision Patients with systemic disease, alcohol and opioid dependency or chronic pain and/or those with contraindication to regional anaesthesia were excluded
Interventions	Treatment groups: lumbar epidural analgesia (L2‐L3 or L3‐L4; catheter advanced 4 to 5 cm passed the needle tip) with 10 mL of 0.25% bupivacaine and 2 mcg/kg of fentanyl 20 minutes before (n = 20) or after surgical incision (n = 20) Control group: 10 mL saline through epidural catheter before surgical incision (n = 20) All participants had an epidural catheter installed and tested with 3 mL of 2% lidocaine. Anesthesia was induced with thiopental 7 mg/kg and vecuronium 0.02 mg/kg and maintained with nitrous oxide 50%, isoflurane 0.5% to 1.5%
Outcomes	Pain scores (0 to 10) at 6, 24 and 48 hours after surgery
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"sealed envelope technique"
Allocation concealment (selection bias)	Low risk	"sealed envelope technique"
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 reported
Selective reporting (reporting bias)	Low risk	All results provided
Other bias	Low risk	Groups well balanced