This study tracks the long-term development of premature infants to examine how birth profiles, risk factors, and physical functioning influence their activities, participation, and quality of life. It also identifies predictors of functional outcomes, evaluates assessment tool sensitivity, validates the General Movements Assessment (GMA) as a prognostic tool, and compares findings with the Taiwan Infant Development Database. The study hypothesizes that birth conditions and postnatal complications predict differences in development and well-being, that risk factors and physical function relate to participation and quality of life, and that the GMA will show reliable validity across disability categories.