Published in August of 2008, WAIS–IV is the most widely used intelligence test for adults in the world. Substantive changes were made to the WAIS-IV from the WAIS-III leaving clinicians with questions as to how to use and interpret the measure effectively. Written by the creators of the new test, this book serves as the ultimate insider's guide to the new test, providing users with the kind of access to norms and data that would be unavailable to any subsequent book on clinical use of this measure.
WAIS-IV IQ LEVELS, DESCRIPTIVE CLASSIFICATION AND PERCENTILE RANK IQ Level Descriptive Classification Percentile 130+ Very Superior 98 - 99.9 120 to 129 Superior 91 - 97 110 to 119 High Average 75 - 90 90 to 109 Average 25 - 73 80 to 89 Low Average 9 - 23 70 to 79 Borderline 2 - 8.
- The Wechsler Adult Intelligence Scale – 4th Edition (WAIS-IV) is an individually administered clinical instrument designed to assess the cognitive ability of adolescents and adults. This updated version provides subtest and composite scores that represent intellectual functioning in specific cognitive domains, as well as a composite score.
- WAIS-IV Administration and Scoring Manual (Wechsler Adult Intelligence Scale - Fourth Edition) (Spiral-bound) Spiral-bound – January 1, 2008 by David Wechsler (Author) 4.6 out of 5 stars 3 ratings.
The book discusses the changes made between 3rd and 4th editions along with an FAQ and answers about use and interpretation. The reader is instructed how to interpret composite scores, and everything needed to use and interpret two entirely new composite scores: the General Ability Index (GAI), and the Cognitive Proficiency Index (CPI). This information does NOT appear in the manual accompanying the test.
The second section of the book focuses on WAIS–IV use and interpretation with special clinical applications and populations, including with multicultural clients, in neuropsychological settings, with individuals experiencing psychological disorders, and with older adults. The editors and chapter authors have exclusive access to proprietary WAIS–IV data to run advanced analyses and provide information beyond what is offered in the WAIS-IV manual.
TRANSCRIPT
AppendixASTEP 1.
A.1:WAISIVInterpretiveWorksheet
1
Report the Persons WAIS-IV Standard Scores (FSIQ and Indexes) and Subtest Scaled Scores.
For IQ and indexes, report standard score, confidence interval, percentile rank, and descriptive category. For subtests, report scaled scores and percentile ranks only. (See Rapid Reference 5.2 for descriptive categories.) STEP 2. Step 2a. Determine the Best Way to Summarize Overall Intellectual Ability. To determine whether the FSIQ is interpretable, subtract the Lowest Index from the Highest Index. Is the difference < 23 points? Y or N
Highest Index Standard Scores:
Lowest
Difference =
If YES, the FSIQ may be interpreted as a reliable and valid estimate of a persons overall intellectual ability. Proceed directly to Step 3. Step 2b.
If NO, then proceed to Step 2b.
To determine whether the General Ability Index (GAI) may be used to summarize overall intellectual ability, calculate the difference between the VCI and PRI. Is the difference < 23 points? Y or N
VCI Index Standard Scores:
PRI
Absolute Difference =
Wais-iv Description
If YES, the GAI can be calculated and interpreted as a reliable and valid estimate of the persons overall intellectual ability.
If NO, then proceed to Step 3.
To calculate the GAI, sum 6 subtest scaled scores of the 3 VCI subtests and 3 PRI subtests, and locate the GAI that corresponds to this sum in Table C.1 of the WAIS-IV Technical and Interpretive Manual (Psychological Corporation, 2008, p. 169). Sum of Subtest Scaled Scores = =
VC Scaled Score +
SI +
IN +
MR +
BD +
VP
GAI
AppendixASTEP 3.
A.1:WAISIVInterpretiveWorksheet
2
Determine Whether the Difference between the Persons GAI and Cognitive Proficiency Index (CPI) Is Unusually Large.
Step 3a. Determine whether the GAI and CPI represent unitary abilities or processes. If you have not already done so in Step 2b, determine whether the GAI represents a unitary ability by calculating the difference between the VCI and PRI. If you completed this calculation in Step 2b, then transfer those results here. Is the difference < 23 points? Y or N
VCI Index Standard Scores:
PRI
Absolute Difference =
If YES, the GAI can be calculated and interpreted as a reliable and valid estimate of the persons overall intellectual ability. Proceed to the next part of this step to determine whether the CPI can be interpreted.
If NO, the GAI-CPI comparison cannot be made. Go to Step 4.
Determine whether the CPI represents a unitary ability by calculating the difference between the WMI and the PSI. Is the difference < 23 points? Y or N If NO, the GAI-CPI comparison cannot be made. Go to Step 4.
WMI Index Standard Scores:
PSI
Absolute Difference =
If YES, then the CPI can be calculated and interpreted as a reliable and valid estimate of the persons overall ability for proficient information processing, through quick visual speed and good mental control.
Step 3b.
Calculate the GAI and CPI if they represent unitary abilities or processes. If the GAI has been calculated in Step 2b, use the value for Step 3c. Otherwise use the tables below to calculate the GAI and CPI.
To calculate the GAI, sum 6 subtest scaled scores of the 3 VCI subtests and 3 PRI subtests and locate the GAI that corresponds to this sum in Table C.1 of the WAIS-IV Technical and Interpretive Manual (Psychological Corporation, 2008, p. 169). Sum of Subtest Scaled Scores = =
VC Scaled Score +
SI +
IN +
MR +
BD +
VP
GAI
To calculate the CPI, sum 4 subtest scaled scores of the 2 Core WMI subtests and 2 Core PSI subtests and locate the CPI that corresponds to this sum in Appendix A.2 the CD-ROM.
AppendixA
A.1:WAISIVInterpretiveWorksheetSum of Subtest Scaled Scores = =
3
DS Scaled Score +
AR +
SS +
CD
CPI
Step 3c. Record the size of the difference between the GAI and CPI in the table below. If it is 9 points or more, it should be considered statistically different (at the p < .05 level). Step 3d. Determine whether the size of the difference between the GAI and CPI is uncommonly large. If it is 19 points or more, it should be considered uncommonly large (occurring less than 10% of the time in the standardization sample). Is the difference significant? 9 points Y or N Is the difference uncommon? 19 points Y or N
GAI Index Standard Scores
CPI
Absolute Difference =
STEP 4.
Select the Wechsler Four-Index Model or the Keith Five-Factor Model.
Step 4 is designed to help you determine if use of the Keith Five-Factor model is appropriate or if the Wechsler Four-Index model should be your choice for interpretation. Answering the next three questions will help you select the appropriate model. Step 4a. Question: Is the person you tested between the ages of 16 and 69? Y or N If no, proceed to Step 5 to interpret data with the Wechsler Four-Index Model. If yes, answer the Step 4b question below.
Step 4b. Question: Did you administer the supplementary subtests, Letter-Number Sequencing, and Figure Weights? Y or N If no, proceed to Step 5 to interpret data with the Wechsler Four-Index Model. If yes, answer the Step 4c question below.
Step 4c. Question: Considering your personal theoretical and clinical foundations, do you choose to interpret the WAIS-IV data with the Keith Five-Factor model? Y or N STEP 5. If no, proceed to Step 5 to interpret data with the Wechsler Four-Index model. If yes, continue to Step 6 to interpret the data with the Keith Five-Factor model.
Determine Whether Each of the Four Wechsler Indexes Is Unitary, and Thus Interpretable
SkipthisstepifyouareinterpretingthepersonsprofileviatheKeithFiveFactorApproach.ProceedtoStep6. Step 5a5d. Calculate the difference between the highest and lowest subtest scaled scores for the VCI, PRI, WMI, and PSI.
AppendixA
A.1:WAISIVInterpretiveWorksheetIs the difference < 5 points? Y or N Y or N Y or N Y or N
4
Highest 5a. VCI Subtest Scores: 5b. PRI Subtest Scores: 5c. WMI Subtest Scores: 5d. PSI Subtest Scores:
Lowest
Difference = = = =
If YES, the ability presumed to underlie the index is unitary and may be interpreted.
If NO, the index cannot be interpreted as representing a unitary ability. Proceed to Step 7 after completing Step 5d.
STEP 6. Determine Whether Each of the Five Keith Factors Is Unitary, and Thus Interpretable. SkipthisstepifyouinterpretedthepersonsprofileviatheWechslerFourIndexmethod.ProceedtoStep7. Step 6a. Calculate the standard scores for the five Keith Factors by summing the scaled scores for the two subtests that comprise each cluster and converting the sum to a standard score using the norms in Appendixes A.3A.6 of the CD-ROM.Scaled Score 2
Factor Gc Gsm Gf Gv Gs VC DS MR BD SS
Scaled Score 1
Sum of Scaled Scores = = = = =
Factor Standard Score
+ + + + +
Wais-iv Manual Citation
IN LN FW VP CD
Step 6b-6f.
Calculate the absolute difference among subtest scaled scores within each of the factors, and determine if the size of the difference less than 1.5 standard deviations (< 5 points).
AppendixA
A.1:WAISIVInterpretiveWorksheetIs the difference < 5 points? Y or N Y or N Y or N Y or N Y or N
5
Factor 6b. Gc 6c. Gsm 6d. Gf 6e. Gv 6f. Gs VC DS MR BD SS
Scaled Score 1
Scaled Score 2
Absolute Difference = = = = =
IN LN FW VP CD
If YES, the ability presumed to underlie the factor is unitary and can be interpreted.
If NO, the factor cannot be interpreted as representing a unitary ability. Proceed to Step 6g after completing Steps 6a6f.
Step 6g.
Determine how many of Keiths Five Factors are interpretable by reviewing the results of Steps 6b6f. Is the number < 3
Number of interpretable Keith factors:
Y or N
If NO, then proceed to Step 7 to interpret the Keith Five Factors.
If YES, only one or two of Keiths factors are interpretable, so we strongly recommend using the Wechsler Four-Index model to interpret the WAIS-IV data. Go back to Step 5 to complete interpretation of the Wechsler Four-Index model. STEP 7. Determine Normative Strengths and Normative Weaknesses in the Index or Factor Profile.
Record the standard score for each interpretable index or factor in the table below. Place a checkmark in the box corresponding to the appropriate normative category for each index or factor. Normative Weakness < 85 Within Normal Limits 85115 Normative Strength > 115
Wechsler Index VCI PRI WMI PSI
Standard Score
AppendixA
A.1:WAISIVInterpretiveWorksheetWithin Normal Limits 85115
6
Keith Factor Gc Gsm Gv Gf Gs
Standard Score
Normative Weakness < 85
Normative Strength > 115
STEP 8. Step 8a.
Determine Personal Strengths and Personal Weaknesses in the Index Profile. Compute the mean of the persons indexes or factors and round to the nearest tenth of a point. Note that all indexes or factors (interpretable and noninterpretable) are included in the computation of the mean. Wechsler Index VCI PRI WMI PSI Sum of Indexes Number of Indexes Mean of Indexes Standard Score Keith Factor Gc Gsm Gv Gf Gs Sum of Factors Standard Score
4
Number of Factors Mean of Factors
5
Step 8b. Fill in the table as follows: Record the interpretable index or factor standard score in column (2). Record the rounded mean of all i