High IQ society

A high IQ society is an organization that limits its membership to people who have attained a specified high score on an IQ test. The oldest, largest, and best-known such society is Mensa International, which was founded by Roland Berrill and Lancelot Ware in 1946. Other societies are Intertel, founded by Ralph Haines in 1966; the Triple Nine Society, founded in 1978; the Prometheus Society; the International High IQ Society, founded by Andrew Nierman [1]; and the Mega Society.

High IQ societies typically accept a variety of IQ tests for membership eligibility, with some of the tests being tests devised by the organization founders and not validated by psychologists.

The highest reported standard score for most IQ tests is IQ 160, approximately the 99.997th percentile (leaving aside the issue of the considerable error in measurement at that level of IQ on any IQ test). IQ scores above this level are dubious, as there are insufficient normative cases upon which to base a statistically justified rank-ordering. High IQ scores are less reliable than IQ scores nearer to the population median.

The entrance criteria for IQ societies vary considerably across both kinds of tests accepted (for example, whether the tests tap primarily numerical, spatial, or verbal abilities, or whether the tests have adequate test security or not) and how high one must score in order to acquire membership.

Some societies, including widely known societies such as Mensa, accept the results of standardized tests taken elsewhere. Those are listed below by selectivity percentile (assuming the now-standard definition of IQ as a standard score with a median of 100 and a standard deviation of 15 IQ points):

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