Macdonald 2011.

Methods	Study type: interventional Study design: randomized, double‐blind, placebo‐controlled, Phase III study Sequence generation: an interactive web response system Allocation: an interactive web response system Blinding: clinical and imaging data were assessed by a masked assessor Incomplete outcome data addressed: reported the number and reason Free of selective outcome reporting: unclear Free of other bias: this trials was funded by Actelion Pharmaceuticals Duration of study: 12 weeks
Participants	Ages eligible for study: 18 to 75 years Genders eligible for study: both Total number of participants: 1157 Location: 102 sites in 27 countries Inclusion criteria: patients had SAH due to ruptured saccular aneurysm secured by surgical clipping. Eligible patients had a diffuse clot (long axis ≥ 20 mm or present in both hemispheres) on admission CT scan and a WFNS grade I to IV SAH before the securing procedure Exclusion criteria: individuals with SAH due to non‐aneurysmal causes, intraventricular or intracerebral hemorrhage without subarachnoid blood, angiographic vasospasm on admission angiography or major complications during the securing procedure were excluded
Interventions	Treatment group: 5 mg/hour clazosentan Control group: placebo
Outcomes	Primary outcome measures: all‐cause mortality and vasospasm‐related morbidity within 6 weeks of aSAH, as defined by at least 1 of the following events: death; vasospasm‐related cerebral infarction; DIND due to vasospasm or neurological signs or symptoms, in the presence of a positive angiogram, leading to rescue therapy Secondary outcome measures: the GOSE score dichotomized as good or poor outcome at week 12 was the main secondary end point. The other secondary end points were the occurrence of the individual components of the composite primary end point and total volume of new or worsened cerebral infarcts of all causes at week 6 after aSAH
Notes	‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	An interactive web response system
Allocation concealment (selection bias)	Low risk	An interactive web response system
Blinding (performance bias and detection bias) All outcomes	Low risk	Clinical and imaging data were assessed by a masked assessor
Incomplete outcome data (attrition bias) All outcomes	Low risk	Reported the number and reason
Selective reporting (reporting bias)	Unclear risk	There was not enough information to permit judgment of the other potential sources of bias
Other bias	Unclear risk	Funded by Actelion Pharmaceuticals