Cattell Infant Intelligence Scale

Purpose: Designed to assess mental ability in children.

Population: Ages 2-30 months.

Score: Mental Age score.

Time: Not reported.

Author: Psyche Cattell.

Publisher: The Psychological Corporation.

Description: The Cattell Infant Intelligence Scale was developed with the intention of being a standardized assessment of mental ability for children aged 2-30 months. Underlying the test is a view of intelligence as being maturationally and genetically controlled. The Cattell proposes to focus on mental development and not on motor development, to be standardized, be objective in scoring, appeal to young children, and provide numerical rather than simply descriptive assessments of mental ability.

Scoring: The test consists of 95 items: five for each month period from 2-12 months, five

for each two-month period during the second year of life, and five for each of the two quartiles of the first half of the third year of life. At each of these age periods, one or two alternate items, which are described as acceptable but somewhat less satisfactory than the standard items, are also included for use as needed. All 95 items are not administered to a given child at a given test administration or age level; only the items necessary to establish basal and ceiling levels are presented in order to obtain a child’s mental age score.

Reliability and Validity: At three months, the reliability estimate obtained by the split-half method and corrected by the Spearman-Brown formula was 0.56. Correlating those scores obtained at three months with scores at 36 months on Form L of the Stanford-Binet resulted in a value of only 0.10. Thus, the scores at age three months show neither statistical reliability or predictive validity. For 6, 9, and 12 months the split-half reliability coefficients were .88, .86, and .89, respectively, and correlations with the Stanford-Binet at 36 months were .34, .18, and .56, respectively. Although reliability estimates reach acceptable levels, the predictive validity scores do not. At ages 18, 24, and 30 months the reliability coefficients were .90, .85, and .71, respectively, with correlations with the Stanford-Binet for 36 months falling at .67, .71, and .83, respectively. Again, acceptable reliability estimates are achieved with the exception of the 30-month score. The predictive validity score at 24, and possibly at 18 months, appears acceptable, but the score at 30 months must be interpreted cautiously, given the low level of reliability at that age.

Norms: The Cattell was developed and tested on a standardization sample of 2,346 examinations made on 274 children enrolled in the Normal Child Series study at the Center for Research in Child Health and Development at the Harvard School of Public Health. Minorities were not included in this sample. This restricted sample, which is neither socioeconomically, ethnically, nor geographically representative of the Unite States population, severely restricts the confidence with which one can usefully apply the scale and interpret the obtained results.

Suggested Uses: The Cattell is recommended for use in clinical, educational, and research settings.