The Intellectual Quotient (CI) is a quantitative or statistical representation of an individual’s score in a standardized intelligence test.
The IQ score has been widely used to compare an individual’s intellectual ability with the average score obtained by a sample of “like” people, usually from the same age group.
- Thus.
- For example.
- It can be said that a person’s intelligence.
- Reflected in the score of an IQ test.
- Is higher (or lower) than the average or typical score of their peers (1).
In 1884, researcher Francis Galton evaluated a large number of people to develop an intelligence test, for this evaluation he tried to measure different characteristics: head size and reaction time are some examples (1).
Through his research, Galton has introduced methods of numerical classification of physical, physiological and mental attributes, so the researcher suggested that a broad set of measures of human characteristics could be significantly described and summarized using two numbers.
Another figure we can point out in attempts to measure the IQ is Charles Spearman, this English psychologist introduced the idea that all aspects of intelligence are linked to each other, this view is very important: he laid the foundations for the expression of the compound of the IQ (1).
The modern era of intelligence testing began shortly after the turn of the century. Alfred Binet and Theodore Simon were tasked with developing a method to identify substantial differences in children’s intelligence level.
The idea was to differentiate those who considered themselves intellectually capable of benefiting from education from those with intellectual problems and should attend special education programs (1).
The methodology was to express a child’s performance as a quotient between the score obtained and the age at which the average child could achieve the same score. The publication of the expanded binet scale of 1908 and the work of the German psychologist Stern gave rise to the concept of mental age (MI).
An IM of 8 means that the child, regardless of their actual age, had an income equal to that of an 8-year-old in a specific task, which led to the creation of the IQ score to represent an IM ratio divided by their chronological age (IC). This relationship has been put into a metric. Thus, mental age was divided by its chronological age and multiplied by 100, resulting in an IQ or IQ score.
Around 1910, Henry Goddard, principal of a New Jersey school for the mentally disabled, introduced the concept of IQ testing in the United States, but the first time IQ scores were part of an IQ test in the United States was in 1916. Until then, Lewis Terman translated the Binet-Simon test, creating the Stanford-Binet test.
During World War I, the U. S. Army developed the Army Alpha and Beta tests, which were intended to assign soldiers’ positions according to their intellectual abilities, also used to exclude those deemed intellectually unsuitable for military service. .
During this time, David Wechsler was appointed military psychologist, who performed psychological tests on people who had failed on the army’s performance scale (3).
In 1932 Wechsler was appointed chief psychologist at Bellevue Psychiatric Hospital in New York, and from that moment on a change in the IQ score began to be raised.
As a result, the meaning of the IQ score has been changed to standard score, which refers to the average score obtained by a sample of healthy age couples (3). This new concept allows the use of the life IQ (4).
Wechsler-Bellevue Form 1 was published in 1939. C was an intelligence measure based on the summary scores of several subtests. In addition to a composite summary, called Full Scale IQ, Wechsler argued that intelligence could be measured more accurately. This can be done by dividing the subtests, but how?
The subtests would be divided in two. First, those that mainly reflect verbal abilities. Second, those that reflect nonverbal intelligence or “performance” skills. Thus, the verbal IQ score and the performance IQ score arose.
Wechsler’s tests and recommendations for describing intelligence have been successful. He then developed an adult test, WAIS (Wechsler 1955), a direct derivation of the Wechsler-Bellevue test and the children’s version (WISC), published in 1949.
Currently, these tests are often used to measure intelligence in a similar way to how a meter would be used to measure the length of a table.
However, the question remains: does an IQ represent someone’s intelligence in a real and precise way?It seems that, little by little, both the concept of IQ and intelligence are evolving and, with this, the way it is evaluated must also evolve. .