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Intellectual disability in children: Evaluation for a cause

Penelope Pivalizza, MD
Seema R Lalani, MD
Section Editors
Marc C Patterson, MD, FRACP
Helen V Firth, DM, FRCP, DCH
Carolyn Bridgemohan, MD
Deputy Editor
Carrie Armsby, MD, MPH


Intellectual disability (ID) is a neurodevelopmental disorder with multiple etiologies that is characterized by deficits in intellectual and adaptive functioning presenting before 18 years of age. ID encompasses a broad spectrum of functioning, disability, and strengths [1]. ID 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. Identifying a cause enables focused interventions, treatments, surveillance, and appropriate counseling, with anticipation of possible medical or behavioral complications and a more specific prognosis [2].

This topic reviews the epidemiology of ID and the evaluation of affected children for a specific cause. Other aspects of ID are discussed separately:

(See "Intellectual disability in children: Definition, diagnosis, and assessment of needs".)

(See "Intellectual disability in children: Management, outcomes, and prevention".)


The following terms are used throughout this topic (see "Intellectual disability in children: Definition, diagnosis, and assessment of needs", section on 'Definitions'):


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Literature review current through: Sep 2016. | This topic last updated: May 26, 2016.
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