How is the diagnosis of Intellectual Disability (ID) performed?

The diagnosis of Intellectual Disability (ID) is primarily conducted through a psychological evaluation. This process involves comprehensive assessments conducted by qualified professionals such as psychologists, who utilize standardized tests to determine an individual's intellectual functioning and adaptive behavior. A speech-language pathologist (SLP) may play a role in assessing communication skills and related aspects of a person with ID, but the final diagnosis requires a broader evaluation typically outside the purview of an SLP alone.

This evaluation includes various tests that measure cognitive abilities and adaptive functioning, and it is essential to follow established guidelines set forth in diagnostic manuals. Other professionals such as pediatricians may identify developmental concerns and refer individuals for psychological evaluations, but they do not typically conduct the diagnostic evaluations themselves. Therefore, while the involvement of many professionals is crucial in understanding and supporting individuals with ID, the definitive diagnosis is made through a psychological evaluation process.