Incremental Validity of the Test for Auditory Comprehension of Language and the Developmental Test of Visual Motor Integration

Predictive validity of the Test for Auditory Comprehension of Language and the Developmental Test of Visual Motor Integration was investigated singly and in combination for a group of preschool children. Both tests were significant predictors of achievement over the two year period (r's typically in high .40s to low .50s). The combination of tests significantly increased the percent of variance accounted for over that provided by the individual tests. That the increases ranged only from 3 to 8% indicated little practical significance in using both instruments as opposed to either test singly.