HCHS/SOL conducts ongoing annual follow-up of cohort participants to collect data on health status, identify major clinical events, and maintain contact with the study cohort. Beginning after the baseline examination, participants are contacted annually, typically by telephone, to obtain updated information on health outcomes, hospitalizations, and vital status. These contacts allow the study to identify incident health events occurring between clinic visits and support longitudinal research on disease development and progression. HCHS/SOL has maintained annual response rates over 80%.
During the annual follow-up, participants (or proxy respondents when necessary) are asked about hospitalizations of primary cardiovascular and pulmonary endpoints since the previous contact. In addition to identifying health events, the annual follow-up helps maintain cohort engagement, update contact information, and support high retention over time. The resulting data provides investigators with longitudinal information that complements clinic examination data and enables prospective analyses of incident outcomes.