Purpose: Designed to measure intellectual abilities and academic achievement.
Population: Ages 2 to 90+
Scales: Reading, Oral Language, Mathematics, Written Language, Knowledge, Supplemental Scores, Intra-Achievement Discrepancies, and Total Achievement
Time: 60-70 minutes.
Authors: Richard Woodcock, Nancy Mather, Kevin McGrew
Publisher: Riverside Publishing
Description: This Woodcock Johnson III - Tests of Achievement (WJ III ACH) updates and expands the WJ-R Tests of Achievement (WJ-R ACH)) with the intension of improving the diagnostic power of the instrument. The WJ III ACH is designed to identify and describe an individualís current strengths and weaknesses. Three oral tests, a diagnostic spelling test and a measure of phonological awareness have been added to evaluate fluency in reading and in math. The other WJ III battery, the WJ III Test of Cognitive Abilities (WJ III COG) is designed to measure general and specific cognitive functions. When these two batteries are administered together, they allow the tester to investigate over-underachievement and to examine patterns of intra-individual discrepancies among cognitive or achievement areas. The batteries of the WJ III COG and WJ III ACH are further classified as standard or extended.
Scoring: Scoring is to be completed during testing to determine basal and ceiling levels. Incorrect responses are recorded verbatim. Raw scores are totaled and converted into age and grade equivalents, percentile ranks, and discrepancy scores with use of the Scoring Tables. Compuscore and Profiles Program are used for all other scoring. The WJ III ACH includes the basic interpersonal communication skill (BICS) scores, and the cognitive-academic language proficiency (CALP) score. These scores are helpful for determining the ability of nonnative speakers of English to function in informal settings and academic settings (e.g., college lectures), respectively.
Reliability: The median reliability coefficient alphas for all age groups for the standard battery of the WJ III ACH for tests 1 through 12 ranged from .81 to .94. For the Extended battery, median coefficients ranged from .76 to .91. The reliability scores for the WJ III meet or exceed standards. The median cluster reliabilities are mostly .90 or higher, and the individual test reliabilities are mostly .80 or higher, and can be used for decision making purposes with support from other sources.
Validity: The technical manual presents a considerable amount of evidence supporting the validity of scores from the test, noting that the earlier versions of the battery have also been shown to have validity The WJ III ACH content is similar to other achievement tests in subject areas and to established practice in schools. Growth curves of cluster scores in the technical manual illustrate expected developmental progressions, with steep growth from age 5 to 25, with a decline thereafter. The most extensively presented data focus on validity evidence from confirmatory factor analyses of test scores from participants age 6 to adult. These analyses show that the seven-factor CHC cognitive model is more closely related to the observed internal structure than six other models derived from other commonly used cognitive batteries. The internal correlations of the entire battery are consistent with relations between areas of achievement and between areas of achievement and ability clusters.
Norms: The normative samples (pre-school, school aged, college and adult) were selected to be representative of the US population, based on geographic distribution, community size and type, and SES, occupational status, sex, race.
Suggested use: The WJ III Tests of Achievement has uses for educational, clinical or research purposes, for diagnosis, educational programming, guidance, program evaluation.