Change your mindset! Mindset characteristics and mindset intervention effects in adolescents with intellectual disabilities

Over the past decades, research on mindsets and the effectivity of mindset interventions in the general population has burgeoned. Previous research demonstrated that mindsets are related to academic and mental health and that mindset interventions generally contribute to youth’s psychosocial functioning. The current dissertation contributed to the existing literature on the concept of mindset and its relation with psychosocial functioning in youth with mild to borderline intellectual disabilities (IQ 50—85), and on the effectiveness of an online mindset intervention developed for this at-risk population. Overall, the findings demonstrated that youth with intellectual disabilities are more likely to hold fixed beliefs about the malleability of emotions and behaviors compared to peers without intellectual disabilities, and demonstrated that the mindset of youth with intellectual disabilities is related to their psychosocial functioning. Furthermore, the current dissertation demonstrated that the online mindset intervention The Growth Factory (1) was feasible in a special education setting and residential health care organization and positively evaluated by the majority of participants, and (2) had beneficial effects on mindsets, perseverance, self-esteem, collaboration, and mental health. Therefore, The Growth Factory showed to be a promising new intervention with the potential to contribute to the existing evidence-based treatment of youth with intellectual disabilities. The results suggest that The Growth Factory can be delivered widely across special education schools and care organizations at relatively low costs and in efficient ways.