This Article Full Text Full Text (PDF) All Versions of this Article: 37/1/123    most recent 01.STR.0000195149.44390.aav1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Elkins, J. S. Articles by Johnston, S. C. Search for Related Content PubMed PubMed Citation Articles by Elkins, J. S. Articles by Johnston, S. C. Pubmed/NCBI databases Medline Plus Health Information Stroke Related Collections Health policy and outcome research Acute Cerebral Infarction

(Stroke. 2006;37:123.)
© 2006 American Heart Association, Inc.

Original Contributions

Recruiting Subjects for Acute Stroke Trials

A Meta-Analysis

From the University of California, San Francisco (J.S.E., T.K., J.R., S.C.J.); Kaiser Permanente San Francisco, California (L.F.).

Correspondence to S. Claiborne Johnston, MD, PhD, UCSF Department of Neurology, Box 0114, 505 Parnassus Ave., M-798, San Francisco, CA 94143. E-mail Clay.Johnston{at}ucsfmedctr.org

Background and Purpose— Recruitment rate is a major determinant of the duration, cost, and feasibility of acute stroke trials.

Methods— We performed a meta-analysis of all randomized, controlled trials of 300 subjects that were designed to evaluate the efficacy of a medical intervention for the treatment of acute ischemic stroke. Data about trial recruitment, organization, and inclusion/exclusion criteria were abstracted independently by 2 reviewers who applied predefined criteria. Recruitment efficiency was defined as the number of subjects enrolled per study center per month of recruitment.

Results— Of 32 trials meeting inclusion criteria, the average recruitment efficiency was 0.79 subjects per center per month (range 0.08 to 3.7). Recruitment efficiency did not vary by geographic region (P=0.36), but trials conducted in 1 country had more efficient recruitment than international studies (P=0.03), and recruitment efficiency declined with each percentage increase in the total number of study centers (P=0.002). The primary study entry criteria that predicted reduced recruitment efficiency were the maximum allowable time from stroke to study enrollment (P=0.002) and the exclusion of mild strokes (P=0.009). Trials with a treatment window >6 hours had approximately double the recruitment rates of trials that used treatment windows 6 hours (1.03 versus 0.52 patients per center per month).

Conclusion— Recruitment rates for acute stroke trials are influenced by organizational structure and study entry criteria. Characterizing predictors of recruitment may help optimize future trial design.

Key Words: randomized controlled trials • stroke, acute

This article has been cited by other articles:

				S. T. Crowley, G. M. Chertow, J. Vitale, T. O'Connor, J. Zhang, R. M.H. Schein, D. Choudhury, K. Finkel, A. Vijayan, E. Paganini, et al. Lessons for Successful Study Enrollment from the Veterans Affairs/National Institutes of Health Acute Renal Failure Trial Network Study Clin. J. Am. Soc. Nephrol., July 1, 2008; 3(4): 955 - 961. [Abstract] [Full Text] [PDF]

				S. Blanton, D. M Morris, M. G Prettyman, K. McCulloch, S. Redmond, K. E Light, and S. L Wolf Lessons Learned in Participant Recruitment and Retention: The EXCITE Trial Physical Therapy, November 1, 2006; 86(11): 1520 - 1533. [Abstract] [Full Text] [PDF]