Diagnosing written language disabilities using the Woodcock-Johnson Tests of Educational Achievement-Revised and the Wechsler Individual Achievement Test.

Abstract

The writing portions of the Woodcock-Johnson Tests of Educational Achievement-Revised and the Wechsler Individual Achievement Test are often administered when establishing eligibility for special education services due to learning disabilities. The scores on these measures are typically regarded as equivalent although little is known about how scores on the two measures differ for the same students. Differences of only a few points, however, may affect eligibility for special education services. These tests were administered to 25 sixth grade students previously diagnosed with learning disabilities in written expression only. Students' Wechsler scores were consistently higher on the overall writing composite, while there was no difference in the mean scores on the language mechanics subtests. The WIAT Written Expression subtest mean, however, was significantly higher than the Woodcock-Johnson Writing Samples subtest mean. Use of the Wechsler test would be less likely to identify children for special education services in written expression when point discrepancy criteria are utilized for eligibility. Clinicians should be cognizant of the effect of the specific test chosen on eligibility outcome.