Mental age and IQ
The concept of mental age (MA) was introduced by Alfred Binet (1905). The mental age is calculated by giving a person/ child a series of tests that are ranked by the age people should be expected to complete them.
The MA can then be used to calculate the intelligence quotient (IQ) by using the following formula (where CA is the chronological age)
IQ = MA/CA x 100
An IQ of 100 results when the mental and chronological ages are equal. IQ tends to be stable throughout life. The first IQ test was called the Stanford-Binet test. The most common IQ test currently in use is the WAIS-IV (Wechsler Adult Intelligence Scale).
The MA can then be used to calculate the intelligence quotient (IQ) by using the following formula (where CA is the chronological age)
IQ = MA/CA x 100
An IQ of 100 results when the mental and chronological ages are equal. IQ tends to be stable throughout life. The first IQ test was called the Stanford-Binet test. The most common IQ test currently in use is the WAIS-IV (Wechsler Adult Intelligence Scale).
