Delineation of cross-domain associations between everyday executive function and adaptive behaviour in Down syndrome and Williams syndrome.

In genetic syndromes such as Down syndrome (DS) and Williams syndrome (WS), difficulties with executive functioning (EF) are a commonly reported feature and a key correlate of long-term success in everyday life. Despite a robust literature in children with these syndromes, it remains unclear how cross-syndrome characteristics of everyday EF relate to adaptive functioning and intelligence among adults with DS and WS, and if these relationships differ between these groups. This study aimed to characterise the profile of strengths and weaknesses in everyday EF using the Behaviour Rating Inventory of Executive Function-Adult Informant Version (BRIEF-A) in older adolescents and young adults with DS and WS.