The main purpose of longitudinal research is to understand how people, behaviors, or situations change over time. Instead of collecting information just once, researchers gather data from the same participants at different intervals. This helps identify long-term patterns, trends, and relationships that might not be visible in a short study. It is commonly used in psychology, healthcare, education, and social sciences. For example, researchers may follow a group of students for several years to understand how their learning abilities develop. https://dataqix.com/longitudinal-research/