Table 1.

Main characteristics of the included studies

Study	Study design	Study duration	Country	Female ratio (%)	Mean age (yr)	Presenting condition	Outcome measurement	Mean follow-up time
Muroi et al. (2008) [13]	Prospective clinical pilot study	NA	Switzerland	80.0	51.5	Fisher Scale 3, 4	GOS ≤3	1 yr
Neuman et al. (2008) [14]	Retrospective observation study	2002–2005	Czech Republic	62.2	52	Hunt & Hess Scale 4, 5	GOS >3	6 mo
Anei et al. (2010) [15]	Retrospective observation study	1997–2001	Japan	71.4	57.6	Fisher Scale 3, 4	mRS >3	3 mo or transfer day
Karnatovskaia et al. (2014) [16]	Retrospective observation study	2007–2012	USA	48.6	51.3	Fisher Scale 3, 4	mean mRS	1–6 mo
Kuramatsu et al. (2015) [17]	Prospective matching study	2010–2012	Germany	66.7	50.5	Hunt & Hess Scale 4, 5, modified Fisher Scale 3, 4, and WFNS scale 4-5	mRS >3	6 mo
Choi et al. (2017) [18]	Random clinical trial	2015–2016	Repulic of Korea	59.1	52.9	Hunt & Hess Scale 4, 5 and modified Fisher Scale 3, 4	mRS >3	3 mo
Shui et al. (2018) [19]	Random clinical trial	2014–2016	China	27.4	44.6	modified Fisher Scale 3, 4	Vasospasm	2 wk
Rhim et al. (2022) [20]	Retrospective observation study	2015–2018	Repulic of Korea	61.1	56.9	Hunt & Hess Scale 4, 5, modified Fisher Scale 3, 4, and WFNS scale 4-5	mRS >3	At discharge
Won et al. (2022) [21]	Retrospective observation study	2015–2018	Repulic of Korea	61.1	57.5	Hunt & Hess Scale 5 and WFNS scale 5 (GCS <7)	mRS >3	At discharge & 3 mo

NA: not available; GOS: Glasgow Coma Scale; mRS: Modified Rankin Scale; WFNS: World Federation of Neurosurgical Societies; GCS: Glasgow Coma Scale.