IQ tests are among the most administered psychological tests.

IQ tests are helpful for some thingslike determining disabilityand less so for others.

Additionally, scoring methods may not be the same from one test to another.

Illustration of cogs in person’s head with lightbulb

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Some commonly used intelligence tests include:

Which IQ test is best or more accurate?

Unfortunately, there is no consensus on this.

What are they used for?

The following is a rough breakdown of various IQ score ranges.

Some tests present scores differently and with differing interpretations of what those scores might mean.

As you look further toward the extreme ends of the distribution, scores tend to become less common.

In the past, scores below 70 were used as a marker to identify intellectual disabilities.

How common are very high IQ test scores?

This involves administering the test to arepresentative sampleof the population that will eventually take the test.

This allows IQ test developers to establishnormsor standards by which individual scores can be compared.

It is important to remember that IQ tests are only one measure of intelligence.

What factors can affect my score?

Many factors can influence IQ and scores can change over time.

Psychologist Robert Yerkes developed IQ tests for the U.S. Army during World War I to test army recruits.

During the 1950s, David Wechsler developed IQ tests for use with children and adults.

These tests remain popular today.

For example, Mensa International offers afree online IQ test.

Kaufman A.IQ Testing 101.

Mensa International.What is IQ?

Stangor C.10.1 Defining and Measuring Intelligence.Introduction to Psychology.Version 2.1.

2020:47-74. doi:10.1017/9781108770422.005

Deary IJ, Strand S, Smith P, Fernandez C.Intelligence and educational achievement.Intelligence.

2007;35:1321. doi:10.1016/j.intell.2006.02.001

Brinch CN, Galloway TA.Schooling in adolescence raises IQ scores.PNAS.

2012;109(2):425430. doi:10.1073/pnas.1106077109

Bartholomew D.Measuring Intelligence.

Breedlove SM.Principles of Psychology.