The effect of grade norms in college students: using the Woodcock-Johnson III Tests of Achievement.

The Woodcock-Johnson III Tests of Achievement grade norms versus age norms were examined in the calculation of discrepancy scores in 202 college students. Difference scores were calculated between the Wechsler Adult Intelligence Scale-3rd Edition Full Scale IQ and the Woodcock-Johnson III Total Achievement, Broad Reading, Math, and Written Language scores. The proportion meeting the substantial discrepancy criterion of two standard deviations plus or minus the standard error of the difference between means was 7.9% using age norms and 37.6% using grade norms. Using mixed analyses of variance, the authors found main effects for type of norm for all difference scores, with grade norms yielding significantly higher difference scores than age norms. A main effect for student status (traditional-age students n = 124, non-traditional-age students n = 78) was found for Total Achievement, Broad Reading, and Math such that traditional-age students had greater discrepancies. Discrepancy scores are contrasted with absolute scores (SS < 85) in the identification of learning disabilities as well. Implications of using grade versus age norms are discussed.