An age-related measure of intelligence level. It is
sometimes defined as 100 times the mental age (MA, determined by a standardized
test) divided by the chronological age (CA). Note that this procedure
establishes the average as 100. Nearly always abbreviated as IQ. Some problems
were encountered with the above method of determining IQ, and most modern tests
use a Deviation IQ. This procedure obtains an IQ by statistical comparison. The
individual's test performance is compared with scores of other individuals the
same age and an IQ is derived. The approximate ranges of intelligence are: Very
Superior (IQ
of 130 and above), Superior (IQ between 120 and 129), High Average
(IQ between 110 and 119), Average (IQ between 90
and 109), Low Average (IQ between 80 and 89), Borderline (IQ between 70 and 79),
Mild Mental Retardation (IQ between 50 and 69), Moderate Mental Retardation (IQ
between 35 and 49), Severe Mental Retardation (IQ between 20 and 34) and
Profound Mental Retardation (IQ below 20). See Wechsler Intelligence Scales;
Educable mentally retarded; Mental retardation; Genius.
