The DSM-5(-TR) expanded the definition of Mild Intellectual Disability (MID) to include adaptive functioning (AF) alongside intelligence quotient (IQ). In this population-based study, we examined behavioural and emotional problems in children with MID and matched controls from early childhood to adolescence. We evaluated how three operationalizations of MID, varying by IQ and AF, influence outcomes. Cognitive assessments and parent-reported problems from 4,643 children from 1.5 to 15 years (T1…
