Development of Overall Identity and Mental Well-Being and Their Associations in Adulthood

Abstract

Little is known about identity development and its associations with mental well-being across adulthood. This study investigated the average development of overall identity and mental well-being, and the links between them. The data were drawn from the Jyväskylä Longitudinal Study of Personality and Social Development, focusing on ages 27, 36, 42, 50, and 61 years ( n  = 266–346). Overall identity was assessed using the Identity Achievement-Diffusion Scale, which was constructed based on semi-structured interviews, covering five life domains. Mental well-being was assessed using self-rated scales of psychological, social, and emotional well-being, as well as anxious and depressive feelings. The data were analyzed using latent growth curve modeling. Overall identity achievement increased nonlinearly from age 27 to 61, with the steepest growth occurring between ages 27 and 42. Life satisfaction and social well-being increased from age 36 or 42 to 61. There were no significant mean-level changes in psychological well-being or in depressive and anxious feelings. The level of overall identity achievement was associated positively with the level of psychological well-being, life satisfaction, and social well-being, and negatively with the level of anxious feelings. This study suggests that identity continues to develop positively and nonlinearly from young adulthood to the beginning of late adulthood. Higher levels of overall identity achievement are positively associated with the level of mental well-being in adults. Further longitudinal research is needed, taking into account both between-person and within-person levels of identity and mental well-being development, as well as their associations.