The Relative Efficiency of Traditional WISC-R IQ’s and WISC-R Factor Scores in Predicting Academic Achievement

The purpose of this study was to determine the relative predictive efficiency of the WISC-R deviation IQ’s and the WISC-R factor scores in predicting academic achievement. Eighty-nine lower-middle to lower class fifth grade students were administered the WISC-R and the Stanford Achievement Test. WISC-R-IQ’s and WISC-R complete estimation factor scores were calculated for each student. Product Moment Correlations were calculated between the SAT stanines and the WISC-R factor scores. Of all of the predictor variable, the Verbal IQ was the most efficient. The results also indicated that two of the WISC-R factor variables. Verbal Comprehension and Freedom from Distractibility, were generally as efficient predictors as the Verbal IQ for math, spelling, reading, and total achievement. The Perceptual Organization factor variable did not prove to be as efficient as the Verbal IQ as a predictor of academic achievement. The relative predictive efficiency of the variable was determined by rank-ordering the validity coefficient from highest to lowest within each achievement area. The highest validity coefficient was used as a reference point from which the magnitude of the difference between it and the remaining coefficients was estimated. In general, the results yielded preliminary evidence that the WISC-R IQ’s were as efficient predictors of academic achievement as the WISC-R factor structure. For example, The Freedom from Distractibility variable has demonstrated promise as a non-intellective aspect of intelligence and achievement, and coupled with the Verbal IQ, could be used in a short form of the WISC-R for predicting academic achievement