Weschler Individual Achievement Test

1. James Becker, Ben Hammond, John Rutledge Weschler Individual Achievement Test

2. Many contributors; authored by “The Psychological Corporation” • For grades K-12 or ages 5-19 • Norm referenced assessment of achievement levels in 8 curriculum areas • Provides initial assessment of strengths and weaknesses through subtest and composite scores • Provides comparison of intellectual ability (as measured by Weschler scales) and achievement levels in the 7 areas of specific learning disabilities that originally a child could be diagnosed in the Education for All Handicapped Children Act (1975-1990 then IDEA) What Is The WIAT?

3. Individual administration only (no group testing) • Time to take test is 30-50 min for kids & 55 minutes for adolescents • Scores interpreted in terms of standard scores, age equivalencies, grade equivalencies • Standard scores can be directly transformed to stanines, normal curve equivalencies, and percentile ranks • Linked to Wechsler scales, which makes it easy to calculate discrepancy between achievement and ability • WIAT has limitations in its usefulness for assessing students with severe disabilities. The manual states that “if the child has a severe disability that interferes with perception of the test stimuli or completion of item responses, test scores may be invalid, unless effective adaptations of test procedures have been successful” (WIAT manual p.165) Administration and Scoring Characteristics

4. Test subjects are required to: • Listen • Read print • Look at Stimuli • Make one-word and multiple-word responses • Write print, point, and mark answers on a sheet Format Characteristics

5. WIAT Examiner Characteristics:Examiner must have graduate level training in administering standardized assessment to be qualified to administer and interpret scores

6. Norms! • Stratified random sample (representative of U.S. population) of 4,252 children in 13 age groups • 2,160 females and 2,092 males, evenly distributed in age groups • Race/Ethnicity of sample group based on U.S. population (per 1988 census data... 1988! Red flag!) • Geographic region: divided into four regions Northeast, North Central, South, and West (sampling based on population of students in each region) • Parental education level stratified into five categories • Normative data gathered in 1988 (Red flag: that’s a long time ago!)

7. Reliability, Stability, & validity • Reliability • above 90% for composite scores in all ages and all categories (some variation by age group) • Stability • above 90% for composite scores in all ages and categories except 85% for reading and math composites (some variation by age group) • Validity • Test items carefully aligned with curriculum and reviewed in the context of school textbooks, teacher surveys, expert opinions, and curricular trends related to age and grade • correlates with achievement • discriminates on the basis of gender, race, ethnicity and other demographic variables • high degree of correlation with other individually administered standardized tests (BASIS, K-TEA, WRAT-R, WJ-R, DAS, PPVT-R)

8. Subtests • Basic Reading • Mathematics Reasoning • Spelling • Reading Comprehension • Numerical Operations • Listening Comprehension • Oral Expression • Written Expression

9. Subtest Examples • Look for these on the left side of intro pages! • Answer page example:

10. Subtest Data Sheets

11. Subtest Data Sheets CONT.

12. Handout Questions?