Technical Adequacy of General Outcome

This study examined three aspects of technical adequacy with respect to two general outcome measures in mathematics. The first two aspects were the effects of aggregating scores and correcting for random guessing on the reli-ability and validity of the measures. The third issue was the extent to which the measures were sensitive to changes in student performance. One hun-dred and five sixth-grade students completed two general outcome measures (basic facts and estimation) weekly for a 10-week period. With respect to aggregation, the results indicated that while fluency with basic facts is mea-sured quite precisely with a single score, aggregation of scores for the esti-mation task increases both reliability and validity. Correcting the estima-tion scores for random guessing is recommended to increase criterion valid-ity. Analyses of sensitivity to growth revealed that although both the fact and estimation measures reflect statistically significant changes across the 10-week period, the fact measure is likely to have greater practical signifi-cance. The article closes with a discussion of the relative merits of the mea