What is the difference between a severe and a profound erudition disability/difficulty?

What is the difference between a severe and a profound erudition disability/difficulty?
Copied and pasted from the site programmed below in the source clause. Bear in mind this is from Ireland but it uses definition from the World Health Organization
A place to get second resouces is from your state's Developmental Disability Council
"Q. What are severe and profound general research disabilities?
A. The World Health Organisation classifies general research disabilities into mild, moderate, severe and profound. The definitions of the degree of disability are usually expressed in expressions of IQ, behavioural competence and/or the need for special services. The IQ span for severe learning disability ranges between 20-35 and for profound erudition disability, it is below 20.
Students with severe to profound disabilities may also hold additional or multiple disabilities, such as physical impairment, audible range impairment, visual impairment, psychological palsy, autistic tendencies, heartfelt disturbance, sensory losses or behaviour problems."
severe is more concerning than a profound
both are handicaps irrespective of classification.
the professionals try to hold different levels within order to address treatment wants.
try checking out learning disabilities net sites for more info.
To be honest, I personally muse it is perception.
However, I believe Educational Psychologists have scales they use. They oral exam and determine where the child come on a specific scale and this is later translated into a score and a subsequent diagnosis.
sorry I can't take out the name of the extent...
"an IQ of less than 20 will be described as have a profound disability, those with an IQ of 20 – 50, a severe study disability.." A quote from the British Institute of Learning Disability (http://www.bild.org.uk).