SUBTEST AND COMPOSITE SCORE COMPARISONS FOR THE DIAGNOSTIC ACHIEVEMENT BATTERY 2ND-EDITION

Interpretation of the variation in an individual student's subtest and composite scores on the Diagnostic Achievement Battery (second editio n) requires the comparison of many values. Although values needed for significance when one is making pairwise comparisons are provided in t he test manual, this method does not control adequately for experiment wise error rate. That is, if five comparisons are made, and each is te sted at the .05 level, the error rate for the combination of five comp arisons is much higher than .05. Use of the Bonferroni correction when one is comparing each score to the mean score is one method that cont rols the overall error rate during interpretation of an individual's t est scores. With this method, the differences required for significanc e when one is comparing an individual's subtest score to the mean of a ll the subtest scores were computed at the .05 and .01 levels in accor dance with the procedure presented by Davis and modified by Silverstei n. Additionally, the same values when one is comparing Composite score s for an individual were computed, An example of the use of the techni que is provided.