Understanding recruitment and retention in neurological research.

Cognitive deficits in participants and the abrupt and traumatic way in which many neurological conditions present are two examples of the unique challenges in recruiting and retaining participants with neurological injury for research studies. The purpose of this investigation was to identify obstacles to recruitment and retention in three ongoing research studies. These studies involve persons with neurological disorders across the continuum of care, from those newly diagnosed and with emergent presentation to those with more established chronic neurological conditions. For this analysis, we evaluated the effectiveness of the strategies employed to improve participation rates. The first study was a project funded by the National Institutes of Health designed to identify biomarkers of vasospasm in persons (n = 496) with aneurysmal subarachnoid hemorrhage who presented to the neurovascular intensive care unit (National Institute of Nursing Research, R01 NR004339). The purpose of the second study was to examine biobehavioral interactions in family caregivers (n = 59) of persons with a primary malignant brain tumor recruited in the community setting. The third project involved recruiting persons (n = 1,019) within an outpatient neurosurgical center to participate in a research registry. To determine differential effectiveness of strategies, consent and attrition rates were calculated at serial points over time in three studies, and recruitment and retention strategies were compared. Sentinel time points in participants' disease trajectories played a key role in determining whether those who were approached to participate gave consent and were retained, particularly in the studies involving persons with aneurysmal subarachnoid hemorrhage (consent = 85%; retention = 89%) and persons with primary malignant brain tumors and their caregivers (consent = 68%; retention = 83%). In addition, several specific recruiter and interviewer training techniques were associated with higher recruitment and retention. Targeted strategies to improve participation rates are vital for neuroscience nurses involved in any aspect of clinical research, including those who conduct studies, assist with data collection, and recruit potential participants.