Assessment of anxiety and behavior disorders among autistic children and youths with intellectual and developmental disabilities

There is a debate regarding the use of instruments that were originally developed for neurotypical populations and subsequently applied to neurodiverse populations. One concern is the risk of downplaying the complex presentation of mental health (MH) symptoms in individuals who are neurodiverse. In this study, we sought to explore MH disorder construct convergence across broad-band instruments developed for people with autism (ASD) or developmental disabilities (IDDs) (i.e., ASD/IDD instruments) and a non-ASD/IDD instrument based on established diagnostic taxonomy. In total, 121 children with IDDs (full scale IQ M =80.8, SD =20.6), including those with ASD, participated. The conceptual overlap between emotional and behavioral subscales from the Developmental Behavior Checklist (DBC), Aberrant Behavior Checklist (ABC), and Psychopathology in Autism Checklist (PAC), on the one hand and emotional and behavioral diagnoses derived from the Developmental and Well-Being Assessment interview (DAWBA), on the other hand, was examined. Subscales from the DBC, ABC, and PAC showed adequate and good correspondence with anxiety disorders and oppositional conduct disorder diagnoses, respectively, derived from the DAWBA. There were meaningful correlations between lower adaptive communication skills/IQ and ASD/IDD instrument subscales reflecting stereotyped and repetitive motor movements, pica, and self-injurious behavior. The ASD/IDD tools showed acceptable MH disorder construct convergence with a non-ASD/IDD diagnostic interview. As they perform well, instruments developed for people with ASD/IDD should be given priority in initial MH assessments. • A head-to-head comparison of different mental health instruments is lacking. • The interrelation between mental health constructs was examined. • The population included children and adolescents with neurodevelopmental disorders (NDDs). • Tools developed for people with NDDs corresponded with criteria-based diagnoses. • In mental health assessments, tools developed for NDDs should be given priority.