UCLA

Prior research supports that the transition to adulthood marks a vulnerable developmental period, marked by pervasively poor outcomes, for individuals with developmental disorders (DD), such as intellectual disability or autism spectrum disorder (e.g., Shattuck et al., 2012; Eaves & Ho, 2008; Bouck, 2012; Young-Southward, Philo, & Cooper, 2017). However, psychosocial and contextual correlates of successful transitions have not yet been thoroughly examined. The current dissertation sought to address this gap in the literature, with a particular focus on mental health (Study I) and social support (Study II). Both studies utilized a singular participant sample (N=93) consisting of typically developing (TD) young adults, young adults with autism spectrum disorder (ASD) with or without cognitive impairments, and young adults with intellectual disability (ID), all of whom were part of a larger longitudinal study. Consistent with previous research, our results indicated that young adults with DD, and especially those with ASD, reliably fared worse than young adults with TD across a variety of outcomes. Results indicated that both mental health and social support in young adulthood explain variability in concurrent functional transition outcomes (e.g., independence, professional involvement). Adolescent predictors of both young adult mental health and young adult social support were also identified, highlighting targets for intervention that may bolster successful transitions to adulthood for all.