De Pietri 2006.

Methods	RCT Approved by the ethics committee and written informed consent obtained Setting: Italy Funding: unspecified
Participants	50 adult patients of both sexes, ASA 1 and 2, scheduled for liver surgery.
Interventions	Treatment group: TEA (T9‐T10 or T10‐T11) with ropivacaine 0.2% for 96 hours or longer (n = 25) Control group: intrathecal morphine 0.2 mg followed by IV PCA with morphine (n = 25) General anaesthesia for all participants
Outcomes	VAS at rest at 8, 24 and 48 hours VAS on coughing (taken as on movement) at 8, 24 and 48 hours
Notes	"Patients were evaluated for post‐dural puncture headache and radicular back pain; muscle weakness and sensory deficit, as early signs of spinal cord compression caused by hematoma, were also evaluated"
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomly allocated to 2 groups by a computer‐generated list
Allocation concealment (selection bias)	Unclear risk	Not mentioned
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Postoperative clinical monitoring of participants and evaluation of VAS were managed by investigators blinded to the analgesic technique used
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Postoperative clinical monitoring of participants and evaluation of VAS were managed by investigators blinded to the analgesic technique used
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up mentioned: "no patient was excluded from the study"
Selective reporting (reporting bias)	Low risk	All results reported
Other bias	Low risk	Groups well balanced