RACE OF REHABILITATION CLIENTS AND PSYCHOMETRIC TEST SCORES IN THE PREDICTION OF VOCATIONAL POTENTIAL (WIDE RANGE ACHIEVEMENT TEST, GATES-MCGINITIE READING TEST, STANDARD PROGRESSIVE MATRICES (SPM)).

Abstract

This study investigated differences among racial groups and between sex groups on psychometric test performances, demographic data, and vocational potential ratings of an adult rehabilitation client sample. Also, the psychometric and demographic variables were included in discriminant function equations to predict the vocational potential ratings of the white, Hispanic, and black groups and of the total sample. The sample in this study was composed of 99 adult rehabilitation clients who completed comprehensive vocational evaluations between January, 1980, and July, 1983. Each case included complete psychometric and demographic data. Also, a vocational potential rating based on this data, other aptitude and ability testing, work sample performances, behavior observations, and other information obtained by the vocational evaluator was reported for each case. Analysis of variance procedures found no significant differences between the male group and the female group of the total sample on the psychometric and demographic variables, or on the cumulative vocational potential rating. Significant differences were found among the racial groups on mean performance of reading comprehension and arithmetic computation, and on years of education attained. Tukey HSD procedures specified that these differences exist between the white group and the Hispanic group on reading comprehension, between the white group and the black group on arithmetic computation, and between the white and black groups and the hispanic group on years of educaton attained. Also, no significant differences were demonstrated among the racial groups on general mental ability, age, or cumulative vocational potential ratings. Discriminant function analysis procedures applied the psychometric and demographic variables to the prediction of vocational potential ratings of the racial groups and of the total sample. Observation of the resulting prediction equations indicated that some external bias may exist in the use of these equations for predicting vocational potential in white, Hispanic, and black groups. Also, no single predictor variable was the primarily selected variable in all of the discriminant function equations of vocational potential ratings in the total sample. Overall, the predictive power of the discriminant function equations was not sufficient to recommend their use in clinical practice.