Sauter 2008.

Methods	RCT, parallel design
Participants	80 patients, ASA I ‐ II, scheduled for elective forearm or hand surgery Exclusions: not detailed (inclusion criteria: ASA I or II; weight 50 ‐ 100 kg; normal neurological status; co‐operative)
Interventions	Ultrasound (n = 40) versus peripheral nerve stimulation (n = 40) Interscalene brachial plexus block of musculocutaneous, radial, median, ulnar and antebrachial cutaneous nerves with 0.6 ml/kg mepivacaine with epinephrine in both groups Ultrasound: 5 ‐ 8 MHz curved probe (Sonosite); endpoint ‐ spread local anaesthetic around all cords or spread from 3 o'clock to 11 o'clock around artery. Multiple injections permitted Nerve stimulation (Stimuplex): 0.1 msec duration, frequency 2 Hz; starting current 1.5 mA; endpoint ‐ motor response in finger or hand from posterior or middle cord at 0.2 ‐ 0.5 mA. Single injection
Outcomes	Supplementation rate (need for local anaesthetic block supplementation, sedatives/analgesics, or GA) Adequacy of block (assessed with sensory testing of all 5 nerves. "Block sufficient for surgery") Block onset time Block performance time (from needle insertion until finishing LA injection; in ultrasound group also included "prescan time") Complications Number of attempts (needle passes defined as withdrawal and subsequent reinsertion of at least 2 cm) Participant discomfort
Notes	Registered in clinicaltrials.gov Data for block performance time not presented as mean (SD) and therefore not possible to combine in this review
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random numbers; permuted blocks
Allocation concealment (selection bias)	Unclear risk	Sealed envelopes opened immediately before block performed. No additional details
Blinding of participants and personnel (performance bias):adequacy of block, need for supplementation	High risk	Not possible to blind anaesthetist
Blinding of participants and personnel (performance bias):Complications	High risk	Not possible to blind anaesthetist
Blinding of participants and personnel (performance bias): time outcomes	High risk	Not possible to blind anaesthetist
Blinding of participants and personnel (performance bias): Patient discomfort	High risk	Not possible to blind anaesthetist
Blinding of outcome assessment (detection bias): adequacy of block, supplementation of block	Low risk	Assessed by blinded observer
Blinding of outcome assessment (detection bias): Complications	Unclear risk	Unclear who assessed this outcome and whether blinded
Blinding of outcome assessment (detection bias): time outcomes	Unclear risk	No details of who assessed these outcomes and whether blinded
Blinding of outcome assessment (detection bias): Patient discomfort	High risk	Participant not blinded to group allocation
Incomplete outcome data (attrition bias) All outcomes	Low risk	Only 1 loss, low attrition rate
Selective reporting (reporting bias)	Low risk	Protocol details published in clinicaltrials.gov. NCT 00321425. Outcomes appear to be reported
Baseline characteristics	Low risk	Baseline characteristics comparable
Funding sources	Low risk	None apparent
Operator expertise	Unclear risk	2 anaesthetists experienced in both techniques