What is a longitudinal study?

A longitudinal study is characterized by its research design that follows participants over an extended period of time, allowing researchers to collect data at multiple points throughout the study. This approach enables the examination of changes and developments in participants' characteristics or behaviors, which can lead to insights about trends, progression, or the impact of specific variables over time.

By observing the same participants at different stages, researchers can better understand causal relationships and the long-term effects of certain factors, which is not possible with studies that only capture data at a single point in time. This makes longitudinal studies particularly valuable in fields like psychology, education, and health, where understanding change is essential.

The other options describe different research approaches or focuses. For example, studies that focus on short-term outcomes or that evaluate data from multiple populations do not capture the longitudinal aspect of tracking changes over time, while studies relying solely on retrospective findings do not involve ongoing data collection from the same participants.