RESUMEN
Retaining subjects from disadvantaged populations in long-term studies is necessary to obtain high-quality data. This article presents cumulative retention rates from a 5-year prospective cohort study, the Pediatric Pulmonary and Cardiovascular Complications of Vertically Transmitted HIV Infection study. It also presents results of a cross-sectional qualitative survey about factors that induced caregivers to stay in the study. Although the repeated study visits were long and uncomfortable, cumulative retention among the 298 HIV-infected children was 80%. Incentives considered important by the caregivers included phone contact with nurse coordinators, nurse coordinators accompanying the caregiver and child during visits, phone reminders for appointments, help with scheduling, meals and transportation, access to health care, and relationships with staff. Thus, the high follow-up rate was in part due to nurses' efforts to reduce the study's burden on the families, provide tangible and intangible incentives, and establish personal relationships with families.