IQ reference chart

IQ reference charts are tables suggested by IQ test publishers to designate IQ score ranges as various categories.[1] As reference charts, they are not to be taken as absolute or precise. All IQ tests show variance in scores even for the same test-taker retested on the same test, and also variance in scores among IQ tests from different publishers. Category labels for IQ score ranges are specific to each brand of test and are arbitrary.

Contents

Terman classification

Lewis Terman, developer of the Stanford-Binet intelligence test, chose the category ranges for score levels on that test using a standard deviation of 16.

Terman's Stanford-Binet Fourth Revision classification
IQ Range ("Deviation IQ") Intelligence Classification
152 and over Genius and near genius
148 - 151 Very superior intelligence
132 - 148 Superior intelligence
116 - 132 Above average intelligence
84 - 116 Normal or average intelligence
68 - 84 Dullness
52 - 68 Borderline deficiency
Below 52 Mental Deficiency

Wechsler classification

The Wechsler Adult Intelligence Scale uses the following category labels,[2] the scores are scaled with a standard deviation of 15.

Wechsler's classification
IQ Range ("Deviation IQ") Intelligence Classification
>= 130 Very superior
120 - 130 Superior
110 - 120 Bright normal
90 - 110 Normal
80 - 90 Dull normal
70 - 79 Borderline
50-55 to ~70 Mild Mental Retardation (MR)
35-40 to 50-55 Moderate MR
20-25 to 35-40 Severe MR
<= 20-25 Profound MR

See also

References

  1. ^ Wechsler 1958, chapter 3
  2. ^ DSM-IV-TR workgroup. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision. Washington, DC: American Psychiatric Association.

Bibliography

Further reading