CLINICAL PEARLS

• Intellectual disability requires both intellectual deficits (IQ testing) and adaptive functioning impairment for diagnosis.
• The most common cause of intellectual disability remains idiopathic, though genetic and environmental factors contribute.
• Early diagnosis and intervention significantly improve long-term outcomes.
• Comorbid psychiatric conditions (e.g., anxiety, ADHD) often present and require separate evaluation and treatment.
• Intellectual disability is distinct from neurocognitive disorders, which involve cognitive decline rather than developmental deficits.