Recruitment and retention of families in clinical trials with longitudinal designs.

The Family Home Visitation Program: Nurse as Coach was a 3-year, National Cancer Institute-funded, multisite, randomized trial of a nursing intervention. It tested the effectiveness of an in-home coaching intervention designed to enhance long-term adjustment of breast cancer's effect on family functioning. We summarize our recruitment and retention experiences, review accrual and retention issues identified from our experiences and those of other researchers, and suggest 24 specific strategies to maximize sample size in future clinical trial studies. Our target sample consisted of 200 women with early stage breast cancer and their male partners and children. We obtained 313 eligible referrals from 91 sites: 217 participants (69.3%) were accrued, 96 families (30.7%) refused, 181 participants (83.4%) were retained, 11 (5.1%) were dropped because of changes in eligibility status or because of scheduling error, and another 25 (11.5%) elected to withdraw.