Trajectories in sense of identity and relationship with life satisfaction during adolescence and young adulthood.

= 17.08 years, range = 12-22 years) in four age groups (early adolescence, middle adolescence, late adolescence, and young adulthood) participated in a three-wave longitudinal study. Latent growth modeling (LGM) analysis revealed that from early to middle adolescence, synthesis continued to be higher than confusion, whereas from late adolescence to young adulthood, confusion tended to be higher than synthesis. The results of the LGM further showed that the change in synthesis was positively related to the change in life satisfaction and the change in confusion was negatively related to it in all age groups. Using latent class growth analysis (LCGA), five identity classes were extracted: high synthesis-low confusion, low synthesis-high confusion, high synthesis-high confusion, low synthesis-low confusion, and moderate synthesis-moderate confusion. LCGA revealed that youth in the high synthesis classes had a higher sense of life satisfaction than did youth in high confusion classes. These findings provide critical insights into trajectories of identity formation and the relationship between identity development and life satisfaction among Japanese youth that can inform future research and programs designed to facilitate their identity formation. (PsycInfo Database Record (c) 2022 APA, all rights reserved).