Background: This study evaluated the role of adaptive behaviour, individual variables (age, gender and problem behaviours) and environmental variables (living arrangements, employment status and city dimension) in affecting the quality of life of individuals with IDD measured from third-party (caregiver) and individuals with IDD' perspective.
Method: For 93 adults with an IDD diagnosis (47% males) aged 19-65 years, third-party and participants' perspective on participants' quality of life (Personal Outcome Scale), adaptive behaviour (Vineland-II scale), problem behaviours (PIMRA and DASH-II scales), and individual and environmental variables were collected.
Results: Adaptive behaviour was the main determinant of quality of life for individuals with IDD. The effect of adaptive behaviour was significant and relevant from both third-party and participants' perspectives. Problem behaviours had a modest negative impact on the quality of life.
Conclusions: Adaptive behaviour is relevant for planning support and interventions for people with IDD to increase their quality of life.
Keywords: adaptive behaviour; intellectual and developmental disability; problem behaviours; quality of life.
© 2020 John Wiley & Sons Ltd.