Looking for opportunities to co-enroll: The DISCOVERY study experience



      Conducting high-quality stroke trials is complex and costly. Often these trials compete for the attention of researchers and the availability of patients. Enrolling patients in more than one study concurrently has the potential to accelerate recruitment into individual studies. DISCOVERY is a multicenter, inception cohort study of cognitive impairment and dementia following ischemic or hemorrhagic stroke. At the request of site investigators, a DISCOVERY committee reviews individual studies for approval of possible concurrent co-enrollment into DISCOVERY. The purpose of this report is to summarize the characteristics and outcomes of studies reviewed by committee for possible co-enrollment.


      This analysis covers studies reviewed from 07/01/2020 to 04/26/2022 by the Site Management Committee (SMC) of the DISCOVERY Recruitment and Retention Core. Characterization of each study included study type, number and length of follow-up visits, and whether there were protocol-required blood draws, brain imaging studies, or cognitive tests. Studies were scored for patient burden and scientific overlap with Discovery. The primary outcome was SMC approval to co-enroll.


      59 studies were reviewed, and 69.5% (n = 41, 21 clinical trials; 20 observational studies) were found by the SMC to be appropriate for co-enrollment. Higher patient burden and greater scientific overlap with DISCOVERY reduced the rates of approval for co-enrollment.


      A large number of diverse stroke studies are being run concurrently across the DISCOVERY study network, however, about two-thirds of the studies were considered appropriate for consideration of co-enrollment. Future studies should study how co-enrollment might improve trial network efficiency.



      PSCID (Post-stroke cognitive impairment and dementia), CPS (Clinical performance sites), SMC (Site Management Committee), SOD (Scientific Overlap with DISCOVERY score), PB (Patient Burden score)
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        • Myles P.S.
        • Williamson E.
        • Oakley J.
        • Forbes A.
        Ethical and scientific considerations for patient enrollment into concurrent clinical trials.
        Trials. 2014; 15: 470
        • Broderick J.P.
        • Palesch Y.Y.
        • Janis L.S.
        • National Institutes of Health Stroke Net I
        The National Institutes of Health StrokeNET: a User’s Guide.
        Stroke. 2016; 47: 301-303
        • Dennis M.
        • Wardlaw J.
        • Sandercock P.
        • Signorini D.
        • Warlow C.
        Families of trials: the answers to all our questions?.
        Cerebrovasc Dis. 1999; 9: 305-313
        • Rost N.S.
        • Meschia J.F.
        • Gottesman R.
        • Wruck L.
        • Helmer K.
        • Greenberg S.M.
        • et al.
        Cognitive impairment and dementia after stroke: design and rationale for the DISCOVERY Study.
        Stroke. 2021; 52: e499-e516
        • Lei L.K.S.
        • Lam B.Y.H.
        • Lai D.W.L.
        • Bai X.
        • Li J.
        • Zou Z.
        • et al.
        Stability of Montreal Cognitive Assessment in individuals with mild cognitive impairment: potential influence of practice effect.
        J Alzheimers Dis. 2022; 87: 1401-1412
        • Davis J.M.
        • Baer G.R.
        • Portman R.
        • Nelson R.
        • Storari L.
        • Aranda J.V.
        • et al.
        Enrollment of neonates in more than one clinical trial.
        Clin Ther. 2017; 39: 1959-1969
        • Henderson G.E.
        • Churchill L.R.
        • Davis A.M.
        • Easter M.M.
        • Grady C.
        • Joffe S.
        • et al.
        Clinical trials and medical care: defining the therapeutic misconception.
        PLoS Med. 2007; 4: e324
        • Saver J.L.
        • Warach S.
        • Janis S.
        • Odenkirchen J.
        • Becker K.
        • Benavente O.
        • et al.
        Standardizing the structure of stroke clinical and epidemiologic research data: the National Institute of Neurological Disorders and Stroke (NINDS) Stroke Common Data Element (cde) project.
        Stroke. 2012; 43: 967-973
        • Gao G.
        • Gajewski B.J.
        • Wick J.
        • Beall J.
        • Saver J.L.
        • Meinzer C.
        • et al.
        Optimizing a bayesian hierarchical adaptive platform trial design for stroke patients.
        Trials. 2022; 23: 754