Validity of a short form of the category test in relation to age, education, and gender

Data for 289 subjects participating in an ongoing study of neuropsychological test performance were used to evaluate the relationship between age and prediction of performance on the long form of the Halstead-Reitan Category Test (CAT) from a short form developed by Calsyn, O'Leary, and Chaney (1980). The major questions were whether: (a) age, education, or gender would add to prediction of long (Y) from short form scores (X); (b) regression equations would be different for older and younger groups; (c) percent variance accounted for in long form scores by short form scores would be larger for younger as opposed to older subjects. For these relatively healthy subjects, prediction based on the short form was not enhanced in a clinically significantly manner by adding age, education, and gender as predictors. Regression equations for older and younger groups differed in intercept values but not in slopes. Percent variance accounted for in long form scores from short form scores did not differ when separate equations were used for younger and older subjects.