Overview of WASI-II - Clinical Assessment
Transcription
Overview of WASI-II - Clinical Assessment
Overview of WASI-II (published 2011) Gloria Maccow, Ph.D. Assessment Training Consultant Objectives • Describe components of WASI-II. • Describe WASI-II subtests. • Describe utility of data from WASIII. 2 | Copyright © 2011. All rights reserved. WASI-II Kit 3 | Copyright © 2011. All rights reserved. What is WASI-II? • • • Individually administered assessment of intelligence of examinees aged 6 through 90 years. Revision of Wechsler Abbreviated Scale of Intelligence (WASI; Wechsler, 1999). Provides composite scores that estimate Verbal Comprehension and Perceptual Reasoning abilities. 4 | Copyright © 2011. All rights reserved. What is WASI-II? • • • WASI-II is linked to WISC-IV (2003) and WAIS-IV (2008). WASI-II provides tables for estimating IQ score range on the WISC-IV and WAIS-IV. There are 4 subtests on the WASI-II: Block Design, Vocabulary, Matrix Reasoning, Similarities. 5 | Copyright © 2011. All rights reserved. Full Scale-4 and Full Scale-2 6 | Copyright © 2011. All rights reserved. 7 | Copyright © 2011. All rights reserved. Revision Goals • Enhance the link to the WISC–IV and the WAIS–IV. • Increase user-friendliness. • Improve psychometric properties. 8 | Copyright © 2011. All rights reserved. Copyright © 1998 by The Psychological Corporation. All rights reserved. 9 | Copyright © 2011. All rights reserved. When to Use WASI-II • • • Obtain estimates of IQ scores rapidly and efficiently when administration of a full battery is neither feasible nor necessary. Screen to determine if an in-depth evaluation is necessary. Reevaluate individuals who previously received a comprehensive evaluation when time available for retesting is limited. 10 | Copyright © 2011. All rights reserved. When to Use WASI-II • • • Obtain estimates of current cognitive functioning for individuals referred for psychiatric, psychological, or psychoeducational evaluations Obtain estimates of IQ scores for vocational and rehabilitation purposes Obtain estimates of IQ scores for research purposes, such as pre-experimental matching of cognitive ability. NOTE: In general, the WASI–II FSIQ should not be used for legal, judicial, or quasi-legal purposes (e.g., a statutorily mandated diagnosis or determination of a disability). 11 | Copyright © 2011. All rights reserved. Getting Started • • We’ll be doing a lot of things today, like looking at pictures, answering questions, and working with blocks. . . .... Do you have any questions? 12 | Copyright © 2011. All rights reserved. Chronological Age 13 | Copyright © 2011. All rights reserved. Seating Arrangement 14 | Copyright © 2011. All rights reserved. General Administration Directions Start Point Reverse Rule Discontinue Rule Stop Point 15 | Copyright © 2011. All rights reserved. 16 | Copyright © 2011. All rights reserved. Block Design (13 items) • • • The Block Design subtest is designed to measure the ability to analyze and synthesize abstract visual stimuli. A total of 9 items from the WASI were retained and 4 new items were added to improve the floor and ceiling of the subtest. While viewing a constructed model or a picture in the Stimulus Book, the examinee uses redand-white blocks to re-create the design within a specified time limit. 17 | Copyright © 2011. All rights reserved. Vocabulary (31 items) • The Vocabulary subtest includes 3 picture items and 28 verbal items. – For picture items, the examinee names the object presented visually. – For verbal items, the examinee defines words that are presented visually and orally. • Vocabulary is designed to measure an examinee’s word knowledge and verbal concept formation. 18 | Copyright © 2011. All rights reserved. Vocabulary-Changes • • • A total of 20 items were retained from the WASI, and 8 new verbal items were added. Art for the retained picture items was updated. The scoring criteria for the retained items were also revised. In addition, the starting items are now scored 2 or 0; rather than 2, 1, or 0; to reduce the chance of reversal and to shorten testing time. 19 | Copyright © 2011. All rights reserved. Matrix Reasoning (30 items) • • • The examinee views an incomplete matrix or series and selects the response option that completes the matrix or series. The subtest taps fluid intelligence, broad visual intelligence, classification and spatial ability, knowledge of part–whole relationships, simultaneous processing, and perceptual organization. A total of 23 items from the WASI were retained (some had minor art modifications), and 7 new items were added. 20 | Copyright © 2011. All rights reserved. Similarities (24 items) • • • • The Similarities subtest is similar to the Similarities subtests in the WISC–IV and the WAIS–IV, except that the WASI–II subtest includes low-end picture items to extend the floor of the scale. For the picture items (Items 1–3), the examinee selects the option that shares a common characteristic with the target objects. For the verbal items (Items 4–24), the examinee is presented two words that represent common objects or concepts and describes how they are similar. The Similarities subtest is designed to measure verbal concept formation and reasoning. 21 | Copyright © 2011. All rights reserved. Similarities–Changes • • A total of 13 items from the WASI were retained (some had minor modifications), and 11 are new. The scoring criteria for the retained items were revised. An instructional prompt has been added to the first two verbal items (Items 4 and 5) to ensure the examinee understands the task of the subtest (i.e., identifying similarities as opposed to defining each word). 22 | Copyright © 2011. All rights reserved. 24 | Copyright © 2011. All rights reserved. T Score to Scaled Score 25 | Copyright © 2011. All rights reserved. Descriptive Classifications 26 | Copyright © 2011. All rights reserved. 27 | Copyright © 2011. All rights reserved. 28 | Copyright © 2011. All rights reserved. Ability-Achievement 29 | Copyright © 2011. All rights reserved. Statistical Significance 30 | Copyright © 2011. All rights reserved. Base Rates 31 | Copyright © 2011. All rights reserved. Normative Sample The normative sample included 2,300 examinees divided into 23 age groups, ages 6 through 90 years. Each group had 100 participants. 32 | Copyright © 2011. All rights reserved. Reliability aAverage Subtest/ Composite Average ra Child Sample Average ra Adult Sample BD .89 .91 VC .91 .92 MR .87 .90 SI .89 .91 VCI .94 .95 PRI .92 .94 FSIQ–4 .96 .97 FSIQ–2 .93 .94 reliability coefficients were calculated with Fisher’s z transformation. 33 | Copyright © 2011. All rights reserved. Concurrent Validity Concurrent validity was established with – measures of intelligence: • • • • WASI WISC–IV WAIS–IV KBIT–2 – measures of achievement • Wechsler Fundamentals: Academic Skills 34 | Copyright © 2011. All rights reserved. Confirmatory Factor Analysis Model AGFI RMSEA CFI TLI Total Sample (N=2,300) One-Factor .711 .245 .926 Two-Factor .994 .029 .999 .986 Child Sample (N = 1,100) One-Factor .738 .231 .930 Two-Factor .999 .000 1.000 1.011 Adult Sample (N = 1,200) One-Factor .684 .258 .923 Two-Factor .985 .046 .999 35 | Copyright © 2011. All rights reserved. .969 Special Group Studies • ADHD • Gifted and Talented • Intellectual Disability – Mild and Moderate • Specific Learning Disability – Reading, Math • Traumatic Brain Injury 36 | Copyright © 2011. All rights reserved. Special Group Studies Subtest/ Composite Intellectual DisabilityMild Matched Control Group Diff. p value Std. Diff. BD 29.9 50.1 20.22 <.01 2.39 VC 28.3 49.1 20.78 <.01 3.00 MR 30.0 48.4 18.36 <.01 2.28 SI 30.6 49.5 18.89 <.01 2.44 VCI 66.7 98.8 32.19 <.01 3.00 PRI 65.9 98.6 32.72 <.01 2.61 FSIQ–4 63.9 98.5 34.56 <.01 3.31 FSIQ–2 65.1 97.7 32.58 <.01 3.28 N = 36 aThe Standard Difference is the difference of the two test means divided by the square root of the pooled variance, computed using Cohen’s (1996) Formula 10.4. 37 | Copyright © 2011. All rights reserved. Customer Service 1-800-211-8378 (USA) 1-866-335-8418 (Canada) Webinar-Specific Questions Gloria Maccow, Ph.D. [email protected] Ph 724-766-7692 www.psychcorp.com