Nursing interventions: Maximizing enrollment and retention in community-based randomized clinical trials

Background: As nurse investigators increasingly conduct randomized clinical trials (RCTs) to demonstrate the impact of prevention-based interventions, they may experience enrollment well below that seen in therapeutic trials. Here we describe the challenges to enrollment and retention of children and their families on a community-based 2.5-year RCT.

Methods: At 4 pediatric cancer centers, children with acute lymphoblastic leukemia (ages 4 -18.9 years) and their parents/guardians were invited to participate in an RCT to test a motivation-based physical activity intervention focused on prevention of treatment-related effects. The intervention, which targeted improved physical function, quality of life, and bone mineral density, began within 10 days of the start of treatment and continued until the end of therapy. Patient disposition (ineligible, declined (reasons for declining), enrolled, withdrew (reasons for withdrawal) and contacting study personnel were tracked in a centralized database.

Results: The study's accrual goal (n=76) was met by extending the accrual timeline by 8 months. Of the 211 eligible patients, 89 (42%) patients/families declined to participate and 15 (7%) withdrew after giving informed consent but before the baseline assessment; 29 (14%) families withdrew after the intervention had begun. Study enrollment varied by study personnel who contacted the families (p=0.02, Fisher's exact test). The retention rate, excluding withdrawals for medical reasons, was 33%––100% across study sites.

Conclusion: Patient/family factors, changing community demographics, and study personnel influenced enrollment and retention in a community-based RCT. These factors can be proactively addressed in study design and in disclosure of study information to maximize participation.