WISC V

 wiscv-kit

WISC IV vs. WISC 5 Scores by John Willis

A one page comparison of WISC IV and WISC V scores with the following introduction:

WISC-IV vs. WISC-V scores  If we re-test (or re-re-re-test) with the WISC-V a student who previously took the WISC-IV, I think it is prudent to administer Comprehension, Symbol Search, Information (if the student took it on the WISC-IV), Picture Concepts, Arithmetic (if the student took it on the WISC-IV), and especially Letter-Numberjohn willis Sequencing (so we can compare the WISC-IV WMI with the WISC-V AWMI (or, as Laurie Farr Hanks noticed that it is written in one place on the Record Form, AMWI). I use ±2 scaled score points as an approximation for a 95% confidence interval. There are still the issues of changes in content of the same subtest on the two scales and, of course, the Flynn Effect.

Technical Reports

Technical Report 1:  This report talks about the derivation and use of two expanded scores,  the Verbal VECI score, and the Expanded Fluid Index (EFI).
Expanded Index Scores (Tech Report #1)

Technical Report 2:  This document from Pearson is intended to shed light on the complexities of testing deaf and hard of hearing children by people who have had sufficient training in and knowledge of language and cultural issues for this population. Testing Children who are Deaf or Hard of Hearing (Tech Report # 2)

Technical Report 3: Using the WASI-II with the WISC-V

Technical Report 4: WISC-V Special Group Study: Children with Hearing Differences Who Utilize Spoken Language and Have Assistive Technology

CHARTS AND TEMPLATES

A CHC chart for recording Wechsler V subtest scores and table of Gf-Gc Classification and WISC-V Subtests
WISC V Composition and Gf Gc listing


Critical values for significant differences between the Verbal Comprehension and Nonverbal Indexes including an example for using it

App. Percent of Pop Expected to Obtain WISC V VCI NVI Discrepancies

Tables providing Critical Values for Statistically Significant Differences between the Broad Verbal and Nonverbal Indexes and Critical Values for Statistically Significant Differences between the Verbal Comprehension and Verbal Knowledge Indexes
BVI and VKI tables

A shell template for reporting WISCV scores
NAMEXX1

The handout below was distributed to professionals for professionals at a workshop.  It is NOT an official Psy Corp or Pearson presentation, and it is obviously not intended for non professionals.
ASAIF WISC-V 12.12.14 Handout

Critical Values for Statistically Significant Differences between the Verbal Comprehension and Nonverbal Indexes
App. Percent of Pop Expected to Obtain WISC V VCI NVI Discrepancies

LINKS TO OTHER REFERENCES

The following FAQs are from Pearson’s website
Pearson’s FAQs

Some practitioners have expressed concern as to whether the Index scores are sufficiently reliable, based as they are on only two subtests.   Hypotheses regarding reliability can be validated by consulting the WISC 5 Technical Manual.

Technical and Interpretive Manual Supplement

“This supplementary document provides the results of the special group studies with other measures that were collected as part of the WISC–V standardization but not reported in the WISC–V Technical and Interpretative Manual (Tech Manual).”
WISC V Technical Manual Supplement

Pearson’s home page on the WISC 5.  An advertising blurb with links to ordering information.
Pearson WISC 5

For a more thorough discussion, see the Introduction and Table by John Wllis and Ron Dumont  at:

John-willis-and-ron-dumont-wisc-5-subtests

New Complementary Subtests

Five new complementary subtest have been added to assess cognitive processes important to academic achievement in reading, math and writing, and have shown sensitivity to specific learning disabilities and other clinical conditions. These subtests include a measure of naming facility (Naming Speed and Naming Quantity) and visual-verbal associative memory (Immediate, Delayed and Recognition Symbol Translation).

Expanded and Updated Factor Structure

The test structure includes new and separate visual spatial and fluid reasoning composites for greater interpretive clarity and a variety of levels of composites for interpretive options.

Primary Index Scales include:

  • Verbal Comprehension Index (VCI)
  • Visual Spatial Index (VSI)
  • Working Memory Index (WMI)
  • Fluid Reasoning Index (FRI)
  • Processing Speed Index (PSI)

Ancillary Index Scales include:

  • Quantitative Reasoning Index (QRI)
  • Auditory Working Memory Index (AWMI)
  • General Ability Index (GAI)
  • Cognitive Proficiency Index (CPI)

Complementary Index Scales include:

  • Naming Speed Index (NSI)
  • Symbol Translation Index (STI)
  • Storage and Retrieval Index (SRI)

Scoring and Reporting

WISC-V scoring options include: Q-global, real-time automated scoring on Q-interactive, or manual scoring

Differences Required for Significance When Each WISC-V Subtest
Scaled Score is Compared to the Mean Subtest Scaled Score  by John Willis and Ron Dumont

Editor’s Note:  The tables in John Willis’s explanation may not appear correctly on all devices.  For a printable copy of this section in Word, with original highlighting, click on:  Differences Required by John Willis

When considering strengths and weaknesses among WISC-V scaled scores, examiners may wish to compare subtest scores to the mean of the subtest scores in a group including the subtest of interest.  The tables at the link below, prepared by Ron Dumont, provide the critical values for significance at the .05 and .01 levels.

Ron Dumont’s Table of Significant Differences on the WISC V for All Ages (Click on Link Below)

Differences Required for Significance When Each WISC–V Subtest Scaled Score Is Compared to the Mean Subtest Scaled Score 4.25.16-1

For example, consider these WISC-V Verbal Comprehension subtest scaled scores obtained by Kate.  Depending on the examiner’s attention span, Kate might have taken 2, 3, or 4 Verbal Comprehension subtests, but in any event, these would have been her scores, the sums of her scores, and the means for each group of 2, 3, or 4 subtests.

 

Scaled Scores and Differences from Means

Subtest ss diff ss diff ss diff ss diff
Similarities 12   12   12   12  
Vocabulary 11   11   11   11  
Information       6         6  
Comprehension         11   11  
SUM 23   29   34   40  
MEAN 11.50   9.67   11.33  

10.00

 

Now the examiner compares each subtest to the mean of all of the Verbal Comprehension subtests taken by Kate.  We have shown 2, 3, and 4 subtests, but in reality, the examiner would be dealing with only one column because the examiner would have administered only 2, or 3, or 4 specific subtests.

Kate’s Similarities score of 12 was 0.55 scaled score points above her mean of 11.50 for Similarities and Vocabulary.  If the examiner had also administered Information, Kate’s Similarities score of 12 would have been 2.33 points above her mean of 9.67 for Similarities, Vocabulary, and Information.  If the examiner had also administered Comprehension but not Information, Kate’s Similarities score of 12 would have been 0.67 points above her mean of 11.33 for Similarities, Vocabulary, and Comprehension. If the examiner had administered all four verbal subtests, Kate’s Similarities score of 12 would have been 2.00 points above her mean of 9.67 for Similarities, Vocabulary, Information, and Comprehension.  Again, only one of these groups would actually have been used; the other groups would be ignored.

  Scaled Scores and Differences from Means
Subtest ss diff ss diff ss diff ss diff
Similarities 12 +0.55 12 +2.33 12 +0.67 12 +2.00
Vocabulary 11 –0.55 11 +1.33 11 –.33 11 +1.00
Information       6 –3.67       6 –4.00
Comprehension         11 –.33 11 +1.00
SUM 23 (0) 29 (0) 34 (0) 40 (0)
MEAN 11.50   9.67   11.33   10.00  

The following table is copied from the upper, left corner of Ron Dumont’s table for “All Ages” from the link above.  There are also separate tables for each year of age (e.g., 6:0:0 through 6:11:30).  These are the critical values for the differences between subtest scores and the means of their group of 2, 3, or 4 subtests.

Differences Required for Significance

  VCI, VSI, FRI, WMI, PSI (2, 3, and 4 subtests)
Subtest .05 .01 .05 .01 .05 .01 .05 .01
Similarities 1.33 1.66 1.95 2.39 2.01 2.47 2.33 2.82
Vocabulary 1.33 1.66 1.91 2.35 1.98 2.43 2.28 2.75
Information     2.04 2.50     2.48 2.99
Comprehension         2.29 2.82 2.78 3.35

The critical values are given for significance at the .05 level (a difference too great to occur just by random variation more than 5 times in 100) and the .01 level (a difference too great to occur just by random variation more than 1 time in 100).  If the difference between a subtest scaled score and its group mean is at least as large as the critical value, the difference is statistically significant (unlikely to occur just by chance) at the .05 or .01 level.

The table below shows the differences that were statistically significant.  Differences that are not significant could have occurred just by random variation and should never be considered differences at all.  We should never, ever report that, “There was a non-significant difference between this and that.”  If the difference was not significant it should not be considered a difference.

If Kate took only Similarities and Vocabulary, neither score differed significantly from her mean score for those two subtests.  If Kate took Similarities, Vocabulary, and Information, her Similarities score was significantly higher (p < .05) and her Information score was significantly lower (p < .01) than her mean score for the three subtests.  If, instead, Kate took Similarities, Vocabulary, and Comprehension, none of her subtest scores differed significantly from her mean score for those three subtests.  However, if Kate took Similarities, Vocabulary, Information, and Comprehension, her Information score was significantly lower (p < .01) than her mean score for the four subtests and none of the other three subtests differed significantly from her four-subtest mean.  The examiner would have an indication that Kate might, for some reason, have a limited fund of general information despite otherwise adequate verbal abilities.  The next step would be to seek other information to refute or support this hypothesis.  If the hypothesis turned out to be supported and not refuted by other data, then the examiner could explore possible causes for, consequences of, and interventions to help with that limitation.

Scaled Scores and Differences from Means
Subtest ss diff ss diff ss diff ss diff
Similarities 12 +0.55 12 +2.33 12 +0.67 12 +2.00
      p<.05        
Vocabulary 11 –0.55 11 +1.33 11 –.33 11 +1.00
               
Information       6 –3.67       6 –4.00
      p<.01       p < .01
Comprehension         11 –0.33 11 +1.00
               

In real life, there would be only one set of scores since the examiner would have given only one specific set of 2, 3, or 4 subtests.  If, for example, the examiner had given all four verbal subtests (which would have been a good idea for Kate’s evaluation), the table would look like this.

Verbal Scaled Scores and Differences from Mean
Subtest Scaled

Score

Difference

from Mean

Significance
Similarities 12 +2.00  
Vocabulary 11 +1.00  
Information   6 –4.00 p < .01
Comprehension 11 +1.00  
Sum 40    
Mean 10.00    

Gary Canivez Publications

For those using the WISC-V in research and clinical practice there are now at least two independent studies published that should be considered that deviate considerably from results presented in the technical manual.   (Added August 28, 2016)

Canivez, G. L., Watkins, M. W., & Dombrowski, S. C. (2016). Factor structure of the Wechsler Intelligence Scale for Children–Fifth Edition: Exploratory factor analyses with the 16 primary and secondary subtests. Psychological Assessment, 28 975-986. http://dx.doi.org/10.1037/pas0000238

Dombrowski, S. C., Canivez, G. L., Watkins, M. W., & Beaujean, A. (2015).  Exploratory bifactor analysis of the Wechsler Intelligence Scale for Children–Fifth Edition with the 16 primary and secondary subtests. Intelligence, 53, 194–201. http://dx.doi.org/10.1016/j.intell.2015.10.009

Enjoy.

Gary L. Canivez, Ph.D.
Associate Editor, Archives of Scientific Psychology
Professor of Psychology
Department of Psychology
600 Lincoln Avenue
Eastern Illinois University
Charleston, IL 61920

Gary Canivez Publications

For additional research on the WISC 5 (and other tests)