Mental Age

Mental age (MA) is also known as an age norm, age equivalent score, or test age. It is defined as the age at which an individual performs on an intelligence test (Sax, 1997). For instance, a person who obtains the same number of points on an intelligence test as the average 8-year-old child is said to have a mental age of 8 years. A person's mental age does not necessarily correspond to his or her chronological age. Thus, a 7-year-old who obtains the same number of points as the average 11-year-old is said to have a mental age of 11 years.

The concept of mental age was introduced by Alfred Binet and Theodore Simon in 1908. Binet and Simon measured mental age by developing questions that ...