Standardization of the Capute Scales: methods and results.

The Capute Scales is a 100-item developmental assessment tool to quantitatively measure expressive and receptive language and nonverbal problem-solving skills in infants from birth to 3 years of age. The present multisite study standardized the instrument on a population of 1055 typically developing children balanced for age, sex, and race and generated normative tables to document the instrument's utility. There were no significant performance differences by race or sex. The achieved age levels for individual test items and for total scores were accurately predicted by the age levels assigned to the test items. The conversion of age levels to standard scores was found to be unnecessary because the developmental quotients derived from age ratios did not differ significantly from the derived scores.