• Rolling over, sitting up, crawling, or walking late
• Talking late or having trouble talking
• Slow to master things like potty training, dressing, and feeding themselves
• Difficulty remembering things
• Inability to connect actions with consequences
• Behavior problems such as explosive tantrums
• Difficulty with problem-solving or logical thinking

Intellectual disability is a disorder with onset during the developmental period that includes both intellectual and adaptive functioning deficits in conceptual, social, and practical domains. The following 3 criteria must be met:

Criterion A. Deficits in intellectual functions, such as reasoning, problem solving, planning, abstract thinking, judgment, academic learning, and learning from experience, confirmed by both clinical assessment and individualized, standardized intelligence testing.

Criterion B. Deficits in adaptive functioning that result in failure to meet developmental and sociocultural standards for personal independence and social responsibility. Without ongoing support, the adaptive deficits limit functioning in one or more activities of daily life, such as communication, social participation, and independent living, across multiple environments, such as home, school, work, and community.

Criterion C. Onset of intellectual and adaptive deficits during the developmental period.

Subtypes:

• Global developmental delay
• Unspecified intellectual disability

Specifiers:

• Mild
• Moderate
• Severe
• Profound