Intellectual disability in children: Definition, diagnosis, and assessment of needs
- Penelope Pivalizza, MD
Penelope Pivalizza, MD
- Developmental and Behavioral Pediatrician
- Independent practice, Houston
- Seema R Lalani, MD
Seema R Lalani, MD
- Associate Professor, Department of Molecular and Human Genetics
- Baylor College of Medicine
- Section Editors
- Marc C Patterson, MD, FRACP
Marc C Patterson, MD, FRACP
- Section Editor — Pediatric Neurology
- Professor of Neurology, Pediatrics, and Medical Genetics
- Chair, Division of Child and Adolescent Neurology
- Mayo Clinic College of Medicine
- Helen V Firth, DM, FRCP, DCH
Helen V Firth, DM, FRCP, DCH
- Section Editor — Genetics
- Consultant Clinical Geneticist
- Addenbrooke's Hospital, Cambridge, UK
- Carolyn Bridgemohan, MD
Carolyn Bridgemohan, MD
- Section Editor — Developmental and Behavioral Pediatrics
- Assistant Professor of Pediatrics
- Harvard Medical School
Intellectual disability (ID) is a neurodevelopmental disorder characterized by deficits in intellectual and adaptive functioning that present before 18 years of age . ID is heterogeneous in etiology and encompasses a broad spectrum of functioning, disability, needs, and strengths.ID affects approximately 1 percent of the population. It is an important public health issue because of its prevalence and the need for extensive support services. Its management requires early diagnosis and intervention, coupled with access to health care and appropriate supports.
The definition and diagnosis of ID, including assessment of needs for support, are reviewed here. Other aspects of ID are discussed separately:
Intellectual disability — ID is a state of functioning that begins in childhood and is characterized by limitations in intelligence and adaptive skills. The term replaces and improves upon the older term of "mental retardation" . A variety of other terms are used outside of the United States to describe ID (table 1).
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- Intellectual disability
- Syndromic versus nonsyndromic ID
- Global developmental delay
- CLINICAL FEATURES
- Presenting symptoms
- Associated conditions
- - Medical conditions
- - Other neurodevelopmental disorders and mental health problems
- CLINICAL EVALUATION
- Detailed evaluation
- - History
- - Physical examination
- - Sensory screening
- DIAGNOSIS OF ID AND NEEDS ASSESSMENT
- Adaptive function
- Intellectual function
- - Standardized intelligence tests
- - Interpretation and limitations of IQ testing
- Classification of severity
- SUMMARY AND RECOMMENDATIONS