Moiniche 1993.

Methods	RCT Approved by the ethics committee and informed consent obtained Setting: Denmark Funding: industry
Participants	31 ASA 1 to 2 patients scheduled for elective cholecystectomy performed through a mini‐laparotomy
Interventions	Treatment group: TEA (T7‐T8) with bupivacaine and morphine intraoperatively and for 38 hours after surgery (n =15) Control group: from 2 to 24 hours postoperatively morphine 0.125 mg/kg IM was administered every 6 hours, and from 24 to 48 hours postoperatively every 8 hours (n = 16)
Outcomes	Pain scores at rest at 24 and 48 hours (6‐point scale) Pain scores on movement at 24 and 48 hours (6‐point scale)
Notes	In all participants, subcutaneous infiltration of the surgical field with plain bupivacaine 0.25% 15 mL was performed immediately before surgical incision
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"randomised", 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	One of these participants was excluded because of preoperatively observed orthostatic hypotension (i.e. fall in systolic BP > 20 mm Hg (2.8 kPa), in association with symptoms of dizziness); no other loss to follow‐up
Selective reporting (reporting bias)	Low risk	All results reported
Other bias	Unclear risk	Groups well balanced Not in intention‐to‐treat: 1 participant was excluded because of preoperatively observed orthostatic hypotension (i.e. fall in systolic BP > 20 mm Hg (2.8 kPa), in association with symptoms of dizziness)