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. 2017 Apr 4;2017(4):CD000119. doi: 10.1002/14651858.CD000119.pub4

PREVAIL 2007.

Methods R = blocked and stratified randomisation, telephone to central randomisation system
 Study treatment was not blinded
 ITT
 Follow up: not available for 32 (15 Rx, 17 control) either by withdrawal of consent or loss to FU
Participants International
 994 men, 768 women, mean age 66 years
 100% CT or MRI before entry
 Ischaemic stroke and unable to walk unassisted
 < 48 hours since stroke onset
 NIHSS score 2 or more
Interventions Rx: enoxaparin 40 mg sc once daily
 Control: heparin sc (5000 IU 12‐hourly)
 Duration: 10 days (range 6 to 14)
Outcomes Death
 DVT (systematic venography or ultrasound if venography not possible)
 PE (symptomatic)
 Extracranial haemorrhage
 Intracranial haemorrhage (systematic CT)
 Modified Rankin Scale
Notes Ex: specified by protocol
 FU: 90 days
 Sponsored by Sanofi‐Aventis (Paris, France)
Risk of bias
Bias Authors' judgement Support for judgement
Random sequence generation (selection bias) Low risk The sponsor generated the randomisation schedule in permuted blocks of 4, stratified by baseline stroke severity that was implemented centrally by an independent interactive voice‐response system
Allocation concealment (selection bias) Low risk The randomisation schedule was implemented centrally by an independent interactive voice‐response system
Blinding of participants and personnel (performance bias) 
 All outcomes High risk Not blinded
Blinding of outcome assessment (detection bias) 
 All outcomes Unclear risk Not blinded, but all major outcome events were reviewed blind to treatment allocation by an adjudication committee
Incomplete outcome data (attrition bias) 
 All outcomes Unclear risk Primary outcome data not available for 32 participants, number with missing modified Rankin Scale status not stated
Selective reporting (reporting bias) Low risk Trial registered NCT00077805, protocol‐specified outcomes all reported