What is the primary distinction of severe and profound retardation?

The primary distinction of severe and profound intellectual disability, often referred to in the context of developmental disorders, is indeed characterized by an IQ below 35. Individuals in this category typically exhibit significant limitations in both intellectual functioning and adaptive behavior. This means they may struggle with everyday tasks and require substantial support in various aspects of life.

Severe intellectual disability generally refers to an IQ range from approximately 20 to 34, while profound intellectual disability is indicated by an IQ of 20 or below. These classifications help in understanding the level of support and interventions necessary for individuals to function day-to-day.

While the other IQ ranges mentioned are accurate descriptors of different levels of intellectual disability, they do not pertain to the severe and profound categories. An IQ between 35 and 49 reflects moderate intellectual disability, while an IQ between 50 and 69 corresponds to mild intellectual disability. An IQ above 70 is considered to be within the range of average intellectual functioning. Thus, the defining characteristics of severe and profound intellectual disabilities are best captured by the cutoff of an IQ below 35.