McCarthy Scales of Children’s Abilities

Purpose: Designed to assess the abilities of preschool children.

Population: Children, ages 2.5 - 8.5.

Score: Six scale scores.

Time:(45-60) minutes.

Author: Dorothea McCarthy.

Publisher: The Psychological Corporation.

Description: The McCarthy Scales of Children’s Abilities (MSCA) is a measurement device used to assess the abilities of preschool children.

Scoring: The results of the MSCA produce six scale scores: verbal, perceptual-performance, quantitative, composite (general cognitive), memory, motor.

Reliability: In the MSCA manual, McCarthy provides information on the internal consistency and stability of test scores, as they were obtained from the standardization sample. The internal consistency coefficients for the General Cognitive Index (GCI) averaged .93 across 10 age groups between 2.5, and 8.5 years. Mean reliability coefficients for the other five Index Scales ranged from .79 to .88. The manual includes information on test-retest reliability over a one month interval on a stratified sample of 125 children grouped into three age levels. The average coefficient for the GCI was .80, with correlations ranging from .69 to .89 for the other scales. Other studies of long and short-term stability resulted in stability coefficients for the GCI of .81 and .84, respectively. Stability coefficients of the cognitive scales ranged from .62 to .76 with the Motor Scale emerging as the only scale that lacked stability (r=33).

Validity: According to the manual, the content of the MSCA and the organization of the six scales were determined primarily through "intuitive and functional considerations" based on McCarthy’s extensive teaching and clinical experience. Analyses of the standardization data for five age groups and for separate groups of blacks and whites have given generally good support for the construct validity of the battery for normal children, although each factor did not emerge for every age group. The results also provide evidence that a child’s profile of MSCA Index scores reflect real and meaningful performance in domains of cognitive and motor ability. The major practical implication of these results for test users is that a child’s strengths and weaknesses can be determined through the interpretation of differences on Scale Indexes, as proposed originally by McCarthy.

Norms: The test was standardized on a sample of 1,032 children stratified by race, geographic region, father’s occupational status, and, informally, urban-rural residency, in accordance with the 1970 U.S. Census data. The major problem which has affected test users’ confidence in the meaning of the scores is the exclusion of exceptional children from the standardization sample.

Suggested Uses: The MSCA is a useful aid in screening and diagnostic decisions.