Calculation of Quick Test IQs for Children with Mental Ages Seventeen and above

Abstract

This study concerned the best method for calculating QT IQs for adolescents whose mental ages are 17.0 or above. Included in the study were 30 cleft palate children, 13 of whom had MAs of 17.0 or above and 17 with MAs below 17.0. A comparison of the relative accuracy of calculating the QT IQ using mental age norms and IQ norms was determined by comparing each method with the Wechsler IQs. The results indicate that QT IQs for children whose MAs are 17.0 or above must be interpreted with caution because the MA method overestimates the Wechsler IQ and the AN method underestimates the Wechsler IQ. The MA method is the more accurate of the two as indicated by (1) the nonsignificant differences between the QT, MA IQ and the WFS and WVS and (2) the higher QT-Wechsler correlation for the entire group using the MA method.