It Takes 52 to Recruit One: Recruitment Barriers in Mechanistic Stroke Neurorehabilitation

BACKGROUND Recruitment in stroke neurorehabilitation trials is often difficult, particularly in studies requiring MRI and repeated laboratory visits. The recruitment efficiency was analyzed to identify the major barriers to enrollment in a stroke neurorehabilitation trial. METHODS In this observational screening study, 1201 patients were screened at a neurological rehabilitation center in Germany between October 2023 and February 2026. Recruitment barriers were analyzed using a stepwise recruitment flow approach. RESULTS Of 678 patients with ischemic stroke, 13 were ultimately enrolled (1.9%; 1.1% of all 1201 screened rehabilitation patients). The most common exclusion reasons were strict clinical eligibility criteria (52.2%), travel distance to the study center (23.9%), and predefined age restrictions (17.9%). Recruitment losses occurred across multiple stages of the screening process. CONCLUSION Recruitment in stroke neurorehabilitation trials is strongly limited by restrictive study criteria and logistical barriers. More pragmatic and inclusive study designs may improve recruitment efficiency and better reflect real-world stroke populations.