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Updated: May 9, 2026

Minimally Invasive Endoscopic Intracerebral Hemorrhage Evacuation
Published on: October 15, 2021
Eligibility for randomized trials of treatments specifically for intracerebral hemorrhage: community-based study
Arthur F Fonville1, Neshika Samarasekera, Aidan Hutchison
1From the Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands (A.F.F., Y.B.R.); and Division of Clinical Neurosciences, Center for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom (N.S., A.H., D.P., R.A.-S.S.).
Background And Purpose:
Acute treatments specifically for intracerebral hemorrhage (ICH) are being sought in randomized controlled trials. The treatment effect sizes in ongoing and future trials are likely to be small, necessitating large sample sizes.
Methods:
We searched online trial registries for randomized controlled trials investigating an acute treatment for ICH. For the trials whose eligibility criteria could be assessed in a prospective, community-based ICH cohort study (2010-2011), we quantified the proportions of patients who were eligible and investigated influences on these proportions.
Results:
We applied the eligibility criteria of 17 trials to 166 adults with ICH, of whom between 0.6% (95% confidence interval, 0.1-3.3) to 40% (95% confidence interval, 33-48) were eligible for each trial. Fewer patients were eligible for trials restricted to patients randomized within 12 hours of ICH onset (versus trials with a longer time window; P=0.03) and trials restricting eligibility according to premorbid disability (versus trials without this restriction; P=0.046). Each additional eligibility criterion reduced the portion of eligible patients by 1.3% (95% confidence interval, 0.4-2.2; adjusted R(2)=0.47; P=0.004).
Conclusions:
Less than half of patients with ICH were eligible for current randomized controlled trials. Future trials could maximize enrollment by minimizing the number of eligibility criteria, maximizing the time window for recruiting patients after ICH onset, permitting premorbid disability, and using a simulator to assess the impact of other eligibility critiera (www.dcn.ed.ac.uk/ICHsimulator/).