Stanford-Binet Intelligence Scale: Form L-M, Third Edition

Purpose: Designed to assess cognitive ability.

Population: Ages 2 to adult.

Score: Scaled scores, area scores, and a Composite Score.

Time: (30-90) minutes.

Authors: Lewis M. Terman and Maud A. Merrill.

Publisher: The Riverside Publishing Co.

Description: The third edition of the Stanford-Binet Intelligence Scale by Lewis M. Terman and Maud A. Merrill was published in 1972. It is a wide-range individual test, assessing intelligence from age two through the superior adult level. It is an age scale, requiring subjects to solve problems, give definitions, memorize new material, and use some visual-motor skills at various age levels.

Scoring: This test has twelve subtests: Vocabulary, Comprehension, Absurdities, Verbal Relations, Pattern Analysis, Copying, Matrices, Paper Folding and Cutting, Quantitative, Bead Memory, Memory for Sentences, Memory for Digits. The examiner must establish a basal age of the child and continue testing until a ceiling is reached. Interpretation is based primarily on objective scoring.

Reliability: Reliability of the scale varies at different ages and different IQ ranges. From age 2.5 to 5.5, the reliability coefficients range from .83 for IQS 140-149 to .91 for IQS 60-69. For ages 6 to 13, the coefficients are .91 to .79 respectively, and for ages 14-18 the coefficients range from .95 to .98 respectively.

Validity: Validity of the scale depends on three sources: 1) the choice of items according to mental age on the 1937 scale assures that the new scale is measuring the same thing that was measured in the original 1916 scale; 2) regular increases in mental age from one age to another agreed with increases in percent passing from one chronological age to the next in both forms of the 1937 scale; and 3) biserial correlations were computed for each item of Forms L and M of the 1937 scale. The retention of an item for the 1960 scale partly depended on its correlation with the total score. The mean biserial correlation for the 1960 scale is .66 (range from .61 at young age levels to .73 for the adult levels).

Norms: The standardization group consisted of a representative sample of 2,100 children, with approximately 100 subjects at each Stanford-Binet year level. Unlike the 1960 norms, which did not include nonwhites in the standardization group, the 1972 norms contained nonwhites (including black and Spanish-surnamed individuals) and whites. Subjects were, however, excluded from the normative sample if English was not the primary language spoken in the home.

Suggested Uses: Used for assessment in educational, research, and clinical settings.