What is the primary characteristic of longitudinal studies?

Longitudinal studies are defined by their ability to analyze changes over an extended period. This method involves collecting data from the same subjects repeatedly over a specified timeframe, allowing researchers to observe how changes occur in response to various variables or context. Through this repeated observation, researchers can identify trends, patterns, and causal relationships that may not be evident in cross-sectional studies, which only offer a snapshot at one point in time.

The strength of longitudinal research lies in its capacity to track developments and fluctuations within the same population, which provides insights into how factors influence life outcomes, behaviors, or social conditions over time.