Identifying, recruiting, and retaining seriously-ill patients and their caregivers in longitudinal research

Background: In order to improve the state of science in palliative care, we must increase our ability to document the real-time experience of patients and families as they traverse the end of life. Yet, frequently, prospective measurement is impeded by difficulty with patient identification, recruitment, enrollment, and retention. The palliative care literature is replete with descriptions of studies unable to meet enrollment goals, and that as a result, do not have adequate power to test hypotheses or draw conclusions. Objectives: To review the literature describing difficulties associated with ascertainment, enrollment, and attrition. To outline the successful recruitment methods of a new longitudinal study of patients and their caregivers. Design: A two-year longitudinal study of 240 patients with Stage IV cancer (breast, prostate, colorectal, lung), advanced congestive heart failure (CHF) LVEFB < 40 or advanced chronic obstructive pulmonary disease (COPD) pCO2 > 46, and their caregivers, interviewed monthly for up to two years. Patients were identified using clinical and administrative databases from one geographic region. Results: Representative and successful ascertainment was associated with use of clinical criteria and medical record review versus physician or other provider prognostication, use of recruitment letters from personal physician, recruitment letter content, brochure content, small monetary incentives, refined phone scripts, use of matched ethnicity interviewers, in-home and phone interview strategies, measure selection, patient and caregiver rapport, and on-going staff support (including grief and bereavement). Conclusions: Recruitment to prospective longitudinal studies at the end of life is difficult, but possible. The lessons learned from this study are applicable to future investigators conducting prospective research.