Participants in which type of study can be followed repeatedly over years?

A panel study is characterized by collecting data from the same participants over multiple time points, often spanning several years. This longitudinal approach enables researchers to observe changes over time within the same individuals, which allows for a deeper understanding of causal relationships and the dynamics of change. For example, in a panel study that examines economic behaviors, researchers may follow the same group of participants each year to analyze how their financial decisions evolve in response to various external factors, such as policy changes or economic conditions.

In contrast, a cohort study examines a specific group of individuals who share a common characteristic or experience within a particular time frame, tracking them over time; however, it may focus primarily on specific outcomes rather than repeatedly collecting a broad range of data from the same subjects. Trend studies aggregate information from different individuals at each time point rather than following the same individuals, which limits the ability to understand individual-level changes. Mixed studies combine various methodologies but do not define a clear long-term tracking of a singular group like panel studies do.