What is the Stanford-Binet test?

Introduction

The origin of the idea that intelligence could be tested can be found as early as the 1860’s, following the publication of British naturalist Charles Darwin’s work On the Origin of Species by Means of Natural Selection (1859). Among the concepts addressed in this book, and in his later The Descent of Man (1871), was the idea that the intelligence of animals, including man, could be understood and measured through scientific investigation.

Sir Francis Galton, a British scientist and explorer, who was also Darwin’s cousin, was among the first to adopt Darwin’s ideas for testing. Galton maintained a laboratory in London, England, where visitors could undergo assorted physical or sensory tests. A subject could be observed on the basis of, for instance, ability to interpret musical pitch. Galton believed such physical or sensory abilities reflected intelligence.

The Binet-Simon Test

In 1904, the Commission for the Education of Retarded Children was established in Paris, France, for the purpose of developing a test that could accurately measure levels of intelligence. The concern was that children were being labeled as what was then termed "retarded" not on the basis of mental capacity but because of behavioral problems. An intelligence test could be used to avoid such incorrect labeling.

Alfred Binet believed that what was recognized as intelligence actually represented a combination of factors, including both knowledge gained from school and knowledge obtained from general observations and interactions with others. The Stanford-Binet test represented the first attempt at determining the mental age of a subject as a means of separating children with learning disabilities from those who did not suffer from learning problems. The basis of such testing consisted of a series of mental tasks of increasing difficulty. Children of various ages were assumed to have a certain level of knowledge in dealing with such tasks. The number of correct responses to these questions resulted in the assignment of a certain “mental age” to the child.

As originally developed in 1905 by Binet and his colleague Théodore Simon, the test, known as the Binet-Simon test, consisted of thirty tasks that ranged from manual dexterity to the ability to remember general facts or concepts. Binet initially screened fifty children considered of average intelligence and developed a series of norms, now called the 1905 scale. Children were tested in this manner and received a score reflecting what Binet and Simon considered their mental age.

Terman’s Refinements

In 1912, psychologist William Stern adapted Binet’s work by calculating what became known as the intelligence quotient, or IQ. The IQ score was calculated by dividing the mental age by the chronological age and multiplying by 100. For example, a mental age of ten and a chronological age of ten resulted in an IQ of 100, considered average. A mental age of twelve in a child of ten would result in an IQ of 120, considered somewhat above average.

Experience with administration of the test to thousands of children over many decades has demonstrated that the distribution of scores resembles a symmetrical pattern, a normal distribution or bell-shaped curve. Most children (approximately two-thirds) fall within the middle of the curve, with the remaining children distributed more or less equally in higher or lower ranges.

The test as originally devised by Binet consisted primarily of verbal reasoning, reflecting the purpose of the test as a means to separate children with learning disabilities from those without. In 1916, Lewis Terman of Stanford University increased the length of the test and extended the range of age among the children who served as subjects. The result was the normal distribution of scores that is now characteristic of the results. What now became known as the Stanford-Binet test replaced its predecessor, the Binet-Simon. Terman’s adaptation has undergone several revisions in the ensuing decades.

The most recent version of the Stanford-Binet test, developed in 2003, consists of both verbal and nonverbal items. The verbal portion involves asking the child to explain or define the use of specific objects. The nonverbal portion contains questions that attempt to examine concepts such as quantitative and abstract reasoning, and memory.

Bibliography

Binet, Alfred, and Théodore Simon. The Development of Intelligence in Children. 1916. Reprint. Manchester, N.H.: Ayer, 1983. Print.

Flannagan, Dawn P., and Patti L. Harrison, eds. Contemporary Intellectual Assessment: Theories, Tests, and Issues. 3rd ed. New York: Guilford, 2012. Print.

Gould, Stephen Jay. The Mismeasure of Man. Rev. ed. New York: W. W. Norton, 2008. Print.

Hernnstein, Richard, and Charles Murray. The Bell Curve. New York: Simon & Schuster, 1996. Print.

Kaplan, Robert M., and Dennis P. Saccuzzo. Psychological Testing: Principles, Applications, and Issues. 8th ed. Belmont: Wadsworth, 2013. Print.

Minton, Henry L. Lewis M. Terman: Pioneer in Educational Testing. New York: New York University Press, 1990. Print.

Musso, Mandi W., et al. "Development and Validation of the Stanford Binet-5: Rarely Missed Items and Nonverbal Index for the Detection of Malingered Mental Retardation." Archives of Clinical Neuropsychology 26.8 (2011): 756–67. Print.

Naglieri, Jack A., and Sam Goldstein, eds. Practitioner’s Guide to Assessing Intelligence and Achievement. Hoboken, N.J.: Wiley, 2009. Print.