A study that follows individuals free of a disease into the future represents which type of study?

A study that follows individuals who are free of a disease into the future is classified as a prospective cohort study. This type of study starts with a group of individuals who do not have the disease of interest and follows them over time to observe whether they develop the disease.

In this research design, participants are typically selected based on specific characteristics or exposures, and data is collected at intervals to capture outcomes as they occur. Because the study design focuses on future outcomes, it allows researchers to assess the relationship between exposures or behaviors and the eventual development of disease within the cohort. This method is crucial in establishing temporal relationships, helping to determine whether certain risk factors are associated with the emergence of diseases.

In contrast, other types of studies listed involve different approaches. For instance, a retrospective cohort study examines existing records to assess outcomes after the fact, while cross-sectional studies analyze data at a single point in time, missing the dynamic nature of future disease development. Hence, the classification as a prospective cohort study is essential for capturing the sequence and timing of disease occurrence related to specific exposures or characteristics.