AAIDD is proud to have been a leader in the adoption of the term intellectual disability in the clinical, scholarly, public policy, and education arenas.
The term or name for condition we know today as intellectual disability has changed over time; most recently the condition was primarily known as mental retardation.
On this website are a number of historical documents that use the term mental retardation. While not the language used by AAIDD today, the language of these documents can understood within their historical or legal contexts, and their underlying
concepts, arguments, findings, and recommendations are consistent with the vision and values of the Association.
The three leading scholarly and clinical organizations concerned with this condition, the AAIDD, American Psychiatric Association, and World Health Organization have been in agreement for more than 50 years that the three essential elements for this condition are:
- Substantial limitations in intellectual functioning
- Substantial limitations in adaptive behavior
- Onset during the developmental period