Encyclopedia of Clinical Neuropsychology

2011 Edition
| Editors: Jeffrey S. Kreutzer, John DeLuca, Bruce Caplan

Intelligence Quotient

  • David Norstokke
  • Donald H. Saklofske
  • Mike R. Schoenberg
Reference work entry
DOI: https://doi.org/10.1007/978-0-387-79948-3_1075




The IQ (intelligence quotient) is a quantitative or statistical representation of an individual’s score on a standardized intelligence test. The IQ score has been widely utilized to compare an individual’s intellectual ability with the average score obtained by a sample of “similar” people, usually of the same age group. Thus for example, it is possible to state that a person’s intelligence, as reflected in an IQ test score, is higher (or lower) than the average or typical scores of their peers. There are numerous intelligence tests and various definitions of intelligence, so while the IQ gleaned from a test is akin to a “score” on that test, the interpretation and meaning may vary from test to test ( intelligence).

Historical Background

The Foundations for the IQ Score

In 1884, Galton measured large numbers of people in an attempt to develop a test of intelligence. He measured many qualities in people, such as head size, reaction time, and strength of...

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References and Readings

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • David Norstokke
    • 1
  • Donald H. Saklofske
    • 1
  • Mike R. Schoenberg
    • 2
  1. 1.Division of Applied PsychologyFaculty of Education, University of CalgaryCalgaryCanada
  2. 2.Department of Psychiatry and Behavioral Sciences, University of South Florida College of MedicineTampaUSA