Showing posts with label Woodcock-Johnson. Show all posts
Showing posts with label Woodcock-Johnson. Show all posts

Wednesday, February 26, 2014

Woodcock-Johnson IV (WJ IV) NASP 2014 introduction and overview workshop slide shows

(Click on images to enlarge)

Last week I, together with Dr. Fred Schrank and Dr. Nancy Mather, unveiled the new Woodcock-Johnson IV Battery at the National Association of School Psychologists (NASP) annual 2014 convention in Washington, DC.  We presented a three hour introductory and overview workshop.  NASP members can download the handouts we provided at the NASP website.  It is my understanding that NASP will eventually provide access to a video of the workshop that will allow NASP members to view and earn CEU credits (I am not 100% sure of this; check with NASP--don't email me).

Since the information we presented is now public, we three coauthors wish to provide access to our presentation to others.  The three presentation title slides are below.  Each are followed by a link to my SlideShare account (click this link if you want to see all three listed, as well as all my other PPT modules) where the slide shows can be viewed.  You will note that not all the slides were presented at the workshop session are included, due to test security issues and the pre-publication nature of various technical information from the forthcoming technical manual.

Enjoy.  Also, as coauthors of the WJ IV, we all have a financial interest in the instrument.  A disclosure statement is present in Part 1 of the slides.  My individual conflict of interest disclosure statement can be found at the MindHub web portal.

Additional information can be found at the official WJ IV Riverside Publishing web page. 

 (Click here for Part 1)

 (Click here for Part 2)

 (Click here for Part 3)

Monday, January 13, 2014

The WJ-IV is coming! Stay tunned to IQs Corner for breaking news, insights, new data-based insights, etc.

If you have wondered why I have not posted as much creative and original content at my blog the past 5+ years, it has been due to our work to revise and re-standardize the WJ III battery.  We are rounding the final corner and Riverside Publishing has officially launched the WJ IV web page, where pre-orders, at a special discount, are being currently being taken.

This is a blatant self-promotional post.  I am a coauthor of the WJ III and WJ IV and thus have a financial interest in its sales (see conflict of interest disclosure statement; which needs to be updated to reflect the WJ IV).

I am very proud to have worked on this project and believe that those who conduct psychological and educational assessments will be pleased with many of the revisions, additions, and new features.  You can learn more at the Riverside WJ IV web page link above.

In the not so distant future I will be making many WJ IV-related blog posts to explain the changes, answer questions posted on listservs, and also provide insights based on yet-to-be published analyses of the norm data and special studies.

Monday, March 28, 2011

Cognitive ability domain cohesion-why composite scores comprised of significantly different subtest scores are still valid

Some excellent discussion has been occurring on the NASP and CHC listservs in response to the "Just say no to averaging IQ subtest scores" blog post and report.

An issue/question that has surfaced (not for the first time) is why markedly discrepant subtest scores that form a composite can still be considered valid indicators of the construct domain. Often clinicians believe that if there is a significant and large discrepancy between tests within a composite, the total score should be considered invalid.

The issue is complex and was touched on briefly in our report and in the NASP and CHC threads by Joel Schneider. Here I mention just ONE concept for consideration.

Below is a 2-D MDS analysis of the WJ III Cog/Ach tests for subjects aged 6-18 in the norm sample. MDS also finds structure as does factor analysis. This 2D model is based on the analysis of the tests correlation matrix. What I think is a major value of MDS, and other spatial statistics, is that one can "see" the numerical relations between tests. Although the metrics are not identical, the visual-spatial map of the WJ III tests does, more-or-less, mirror the intercorrelations between tests. [Double click on image to enlarge]

So....take a look at the Gc, Grw, or Gq tests in this MDS map. All of these tests cluster closely together. Inspection of their intercorrelations finds high correlations among all measures. Conversely, look at the large amount of spatial territory covered by the WJ III Gv tests. Also look at the Ga tests (note that a red line is not connecting Auditory Attention, AA, down in the right-hand quadrant with the other Ga tests). Furthermore, even though most of the Gsm tests are relatively cohesive or tight, Memory for Sentences is further away from the other Gsm tests.

IMHO, these visual-spatial maps, which mirror intercorrelations, tell us than in humans, not all cognitive/ach domains include narrow abilities that are highly interrcorrrelated. I call it "ability domain cohesion." Clearly the different Gv abilities measured by the WJ III Gv tests indicate that the Gv domain is less cohesive (less tight) than the Gc or Grw domain. This does not suggest the tests are flawed..instead it tells us about the varying degrees of cohesiveness present in different ability domains.

Thus, for ability domains that are very very broad (in terms of domain cohesion--e.g., Gv and Ga in this MDS figure), wildly different test scores (e.g., between WJ III Spatial Relations, SR, and Picture Recognition, PR) may be valid and simply reflect that inherent lower cohesiveness (tightness) of these ability domains in human intelligence. Thus, if a person is significantly different in his/her respective Gv SR or PR scores, and these scores are providing valid indications of their relative standing on these measured abilities, then combining them together is appropriate and reflects a valid estimate of the Gv domain....which by nature is broad...and people will often display significant within-domain variability.

Bottom line. Composite scores produced by subtests that are markedly different are likely valid estimates of is just the nature of human intelligence that some of these domains are more tight or cohesive than others.
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Dissertation dish: WJ III TBI cognitive profiles by gender

Click on image to enlarge abstract

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Sunday, January 02, 2011

MDS analysis of WISC-IV

It is no secret that I'm a big fan of multidimensional scaling (MDS--especially Guttman's Radex) model as a supplement to factor analysis of cognitive tests. While going thru some of my e-files I found a recent 3D MDS analysis of the WISC-IV. Below is the abstract and final 3D model. Clicking on images should take you to a larger version of the image.

For those interested, the content/stimulus dimension of my proposed cognitive ability assessment design and interpretation matrix is due to my application of MDS to data from the WJ III and the various Wechsler batteries. The complete "beyond CHC theory" presentation can be found at a prior post.

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Sunday, December 19, 2010

IQ tests and theory trends: Google Ngram visualizations

This past week I read a very intriguing article in the New York Times about a new data visualization tool offered by Google-- the Google Books Ngram Viewer. I then ran across a legal blog post where someone had investigated trends in different law terms...and I couldn't help myself but to give it a try.

As described by Robert Ambrogi at the legal blog:

"Using data drawn from the millions of books it has digitized covering the years 1500 to 2008, it lets you see and compare the frequency of words and phrases as they were used in books over a span of years or centuries. As Google puts it: “The Ngram Viewer lets you graph and compare phrases from these datasets over time, showing how their usage has waxed and waned over the years.”

I first had to experiment with how the entered terms worked. The terms are case sensitive. I checked each phrase with a variety of permutations to maximum the "hit rate"...and then ran some phrases together to ascertain and compare trends.

Below are my results with a few comments--the data tend to speak for themselves. I found that most of what I searched for did not emerge until after that is where each graph starts. It is also important to note that the graphs only go up thru would be nice to see the graphs up today

Cool stuff. Double click on each graph to enlarge.

This chart suggests that the cognitive ability domains of Gv (Visual Processing), Ga (Auditory Processing), and Processing Speed (Gs) have become hotter topics than Gf (Fluid Intelligence), Gc (Crystallized Intelligence), Gsm (Short term Memory), and Glr (Long term Retrieval). Interesting.

One very clear observation. Among the non-Wechsler intelligence batteries, the Stanford Binet has dropped dramatically over time, while the "newbies" on the IQ testing block (WJ, DAS, KABC, CAS) have made been the focus of more writing since 1990. Note, "Wechsler Intelligence", when included, is the clear winner across time. I left it out so the trends for the "other" batteries would be more distinct.

As I have written about many times, contemporary Cattell-Horn-Carroll (CHC) intelligence theory has become the consensus theory of intelligence. This interesting graph supports this conclusion, especially from 1997 to 2008. Also, if one clicks on the search term in the summary table, one is taken to a page of the Google books that included the term. Click here to see example for CHC theory.

I think many of the trends noted above are due to emergence of Gf-Gc theory to CHC theory with the publication of the 1989 WJ-R. I've written about this critical theory-to-practice birth period here and here.

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Monday, July 26, 2010

Research brief 7-26-10: CHC theory and measures (WJ III) found invariant (no psychometric bias) across blacks and whites

Kane, H. D., & Oakland, T. D. (2010). Group Differences in Cognitive Ability: A CHC Theory Framework. Mankind Quarterly, 50(4), 318-331.


The Cattell-Horn-Carroll (CHC) model of cognitive ability as represented in the Woodcock-Johnson Tests of Cognitive Ability-III (WJ-III) was examined for Black and White adults matched on various demographic variables. Although Whites performed higher than Blacks (i.e., race differences were found in test scores and accompanying factor means), the results of multisample confirmatory factor analyses found that the same constructs are measured in different groups. Therefore results are directly comparable, and in this sense measured differences can be interpreted as “real” differences on the dimensions that the test is meant to measure.
Part of authors conclusions:
With respect to the primary purpose of this study, although White-Black differences in cognitive ability are affirmed in favor of Whites, these analyses reveal no source of psychometric bias (i.e., differences in loadings, test intercepts, and error variance). Constructs are represented adequately and without undo influence of error. The structural fidelity of the WJ-III factor model is psychometrically sound, making it a suitable instrument for psychologists when estimating general and broad cognitive abilities for individuals and groups. The reported indices of fit (e.g., TLI, GFI, and RMSEA) suggest that the threestratum CHC model fits the WJ-III data fairly well and provides evidence of construct validity. This finding substantiates a growing body of research literature that upholds the WJ-III as a strong representation of CHC theory (e.g., Edwards & Oakland, 2006; McGrew & Woodcock, 2001). Further, the data support Carroll’s (1993) belief that the CHC theory is essentially invariant across racial-ethnic groups. Notably, the group differences in test performance are smaller than in most other studies (e.g., Osborne & McGurk, 1982). This particular result is likely due to the samples being matched by parental education and occupational status. In the US, this kind of control is expected to remove approximately one third of the Black-White difference that may be expected in demographically representative samples (Jensen, 1998;
Lynn, 1998).

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Thursday, July 15, 2010

Current research in Cattell-Horn-Carroll (CHC) based intelligence testing: Special PITS isue is out

I'm excited to announce that the special issue of Psychology in the Schools, Current Research in Cattell-Horn-Carroll-Based Assessment (guest editors where Jocelyn Newton and myself), is now published.  Yippeee.  To be honest, Dr. Newton deserves the major credit....she did all the heavy lifting and I road her coat tails.  Also thanks to Dr. David McIntosh for suggesting and overseeing the special issue

A review of the TOC can be found by clicking here.  A copy of the article (Cattell-Horn-Carroll cognitive achievement relations:  What we have learned from the past 20 years of research) I co-authored with Barb Wendling can be found by clicking here and the introduction to this issue I co-authored with Dr. Newton is available here.

If you do not have access to this journal and would like to read 1 or more of the articles, I'd be willing to privately share PDF copies in exchange for a guest blog post review here at IQ's Corner.  Now how can folks resist such an offer? learn more and to become a guest blogger.  It doesn't get any better.


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Thursday, June 24, 2010

Use of WJ III NU Cognitive and Achievement batteries in Canada: ASB #12 Report now available

ASB #12 Use of the Woodcock-Johnson III NU Tests of Cognitive Abilities and Tests of Achievement with Canadian Populations  is now available for download at the Riverside Publishing web site (click here).

As described at the Riverside web page:
This bulletin examines the use of the Woodcock-Johnson III Normative Update (WJ III NU) Tests of Cognitive Abilities and Tests of Achievement  with a random sample of 310 school-age Canadian students. Results were compared with a matched sample of U.S. subjects selected from the WJ III NU standardization sample using WJ III NU norms. While some minor score differences are reported across the two samples, the study findings generally support the use of the U.S.-based WJ III NU norms with Canadian school-age populations.

Conflict of interest - I am a coauthor of the WJ III battery.  Complete conflict of interest disclosure information is available via a link on the blog roll side bar of this blog.

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Friday, June 18, 2010

Handbook of Pediatric Neuropsychology: Woodock-Johnson III chapter

NOTE -- after making this post I've learned that I may not have had appropriate position to post a link to the PDF copy of the WJ III chapter.  Thus, those URL's have been temporarily deactivated.  I will reactivate if I get clearance.  Sorry.

The forthcoming Handbook of Pediatric Neuropsychology (Dr. Andrew Davis) can now be pre-ordered from Springer Publishing.

A description of the book, at the publisher website, is below:
This handbook covers basic neurodevelopmental research that any pediatric neuropsychologist will need to know. The authors discuss practical issues in pediatric assessment, and provide a comprehensive overview of the most common medical conditions that neuropsycholoigists encounter while dealing with pediatric populations.

The book also describes a variety of professional issues that neuropsychologists must confront during their daily practice, such as ethics, multiculturalism, child abuse, forensics, and psychopharmacology. Also discussed are school-based issues such as special education law, consulting with school staff, and reintegrating children back into mainstream schools.

An incomplete table of contents is available at the website.  The complete TOC is listed includes 95 chapters...yes, that is correct!!!!!  Simply a major tome.

I received an advanced copy of the chapter dealing with the WJ III Tests of Cognitive Abilities (Dr. Fred Schrank).  This chapter is unique in that it is the first comprehensive presentation of research results regarding WJ III cluster and test scores on over 2,200 subjects with a variety of clinical diagnoses (ADHD, anxiety spectrum disorders, head injury, autism spectrum disorders, types of learning disabilities, MR/ID, etc.) who are part of the Woodcock-Munoz Foundation Clinical Data Base.

    Section 1: Development
1    Intrauterine Development of the Central Nervous System
2    Neuropsychological Development of Newborns, Infants and Toddlers (0 to 3)
3    Neuropsychology of Early Child Development (Ages 3 to 5)
4    Neuropsychology of Middle Child Development (Ages 6 to 11)
5    Neuropsychology of Adolescent Development (Ages 12 to 18)
6    Cognitive Development
7    Speech and Language Development
8    Moral Development
    Section 2: Functional Neuroanatomy for Pediatric Neuropsychologists

9    Cells, Synapses, and Circuits
10    Cerebral Vascular Anatomy and its Clinico-Anatomic Correlates
11    The Spinal Cord
12    Functional Neuroanatomy of Structures of the Hindbrain, Midbrain, Diencephalon and Basal Ganglia.
13    Functional Neuroanatomy of the Limbic System
14    Functional Neuroanatomy of the Cerebellum
15    Functional Neuroanatomy of the Cerebral Cortex
16    Plasticity in a Pediatric Population
    Section 3: Pediatric Neuropsychological Assessment
17    Assessment of Premorbid Functioning in a Pediatric Population
18    Neuropsychological Assessment of Newborns, Infants and Toddlers
19    Assessment of Children with Pervasive Developmental Disorders
20    Assessing Diverse Populations with Nonverbal Measures of Ability in a Neuropsychological Context
21    Achievement Tests in Pediatric Neuropsychology
22    Assessing Adaptive Skills in a Pediatric Population
23    Measurement of Attention: Theoretical and Operational Considerations
24    Assessment of Executive Functions in a Pediatric Population
25    Memory Testing in Pediatric Neuropsychology
26    Personality Assessment for a Pediatric Population
27    Assessing Visual-Spatial and Construction Skills in a Pediatric Population
28    Cognitive Assessment System: Redefining Intelligence from a Neuropsychological Perspective
29    The Dean-Woodcock Sensory-Motor Battery
30    Kaufman Assessment Battery for Children-Second Edition
31    Examining and Using the Halstead-Reitan Neuropsychological Test Battery: Is it our Future or our Past
32    The Luria-Nebraska Neuropsychological Test Battery
33    NEPSY-II
34    Stanford-Binet Intelligence Test-Fifth Edition
35    The Wechsler Intelligence Scale for Children-Fourth Edition in Neuropsychological Practice
36    Woodcock-Johnson III Tests of Cognitive Abilities
    Section 4: The Assessment Process for Pediatric Neuropsychologists
37    The Pediatric Diagnostic Interview and Neurobehavioral Evaluation
38    Pediatric Neuropsychological Testing: Theoretical Models of Test Selection and Interpretation
39    Malingering and Related Conditions in Pediatric Populations
40    Delayed and Progressive IQ Decline in Pediatric Patients
41    Writing Pediatric Neuropsychology Reports
42    Conducting Feedback for Pediatric Neuropsychological Assessments
    Section 5: Pediatric Neuropsychological Disorders
43    Pervasive Developmental Disorders
44    Individuals with Intellectual and Developmental Disabilities
45    Reactive Attachment Disorder
46    Attention-Deficit/Hyperactivity Disorder
47    Conduct Disorder and Oppositional Defiant Disorder
48    Developmental Dyspraxia and Developmental Coordination Disorder
49    Pediatric Tic Disorders
50    Eating Disorders
51    Neuropsychology of Pediatric Anxiety Disorders
52    Mood Disorders of Childhood and Adolescence
53    Dyslexia
54    An Overview of Neuroscience Contributions to the Understanding of Dyscalculia in Children
55    Neuropsychology of Written Language Disorders
56    Receptive and Expressive Language Disorders of Childhood
57    Neuropsychology of Auditory Processing Disorders
58    Nonverbal Learning Disabilities: Assessment and Intervention
59    Perinatal Complications
60    Long-Term Outcome Following Preterm Birth
61    Periventricular Leukomalacia (PVL): Pathogenesis and Long-Term Outcomes
62    Spina Bifida and Hydrocephalus
63    Down Syndrome
64    The Dystrophinopathies
65    Sex Chromosome Aneuploidies
66    Neurofibromatosis, Type 1: from Gene to Classroom
67    Endocrine and Metabolic Disorders
68    Pediatric HIV/AIDS
69    Infectious Diseases of the Central Nervous System: Neurobehavioral and Neuropsychological Sequelae
70    Fetal Alcohol Spectrum Disorders
71    Central Nervous System Cancers
72    Pediatric Neuropsychology and Sleep Disorders
73    Neuropsychology and Headache
74    Seizure Disorders
75    Pediatric Neuropsychology of Substance Abuse
76    Toxic Exposures
77    Traumatic Brain Injury in Children and Adolescents
    Section 6: Professional Issues for Pediatric Neuropsychologists
78    The Past, Present, and Future of Pediatric Neuropsychology
79    Cultural Considerations in Pediatric Neuropsychology
80    Ethical and Legal Guidelines for Pediatric Neuropsychologists
81    Functional Behavioral Assessment
82    Professional Issues for Pediatric Neuropsychologists: Behavioral Interventions
83    Neuropsychological Aspects of Child Abuse and Neglect
84    Forensic Pediatric Neuropsychology
85    Neuroimaging and Pediatric Neuropsychology: Implications for Clinical Practice
86    Psychopharmacology for Pediatric Neuropsychologists
87    Neuropsychology of Gifted Children
88    Sport Neuropsychology for Children
    Section 7: Neuropsychology in the Schools
89    Consulting with School Staff
90    Special Education Law and 504 Plans
91    Participating in Case Conferences
92    Curriculum-Based Measurement
93    Response to Intervention (RTI) from a Neuropsychological Perspective
94    Facilitating School Reintegration for Children with Traumatic Brain Injury
95    Developing and Implementing Evidence-Based Academic Interventions

[Conflict of interest Notice- I am a co-author of the WJ III Battery and am also Research Director for WMF]

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Wednesday, April 28, 2010

Dissertation Dish: WJ III Normative Update (NU) vs original WJ III norm scores

Normative comparison for the Woodcock-Johnson III: Tests of achievement in 15 and18 year olds by Cummings, Amber, Ed.S., Marshall University, 2009 , 27 pages; AAT 1481309

This study evaluates the use of the original and updated norms of the Woodcock Johnson-III in making educational decisions. The method of collection involved placing the raw score obtained from the updated norms into the original Compuscore program to see if there is a difference between the two scoring systems. The scores were then placed in a figure to see how much the scores varied from each other. Results of the study showed that there was a 1 to 3 point difference between specific skill areas, with some skill areas obtaining a 5 to 6 point difference. Suggestions are made for Practitioners when using the updated norms.

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Wednesday, April 21, 2010

Beyond CHC: Pushing the edge of the CHC and WJ III envelope--the grand model

The grand unveiling!!!!!!! This is a follow-up to my "Beyond CHC: Pushing the edge of the CHC and WJ III envelop" project. I urge (require, demand?) you to read the prior explanation and view the PPT slides/PDF files previously posted. They provide the necessary background re: the nature of this project.

As a result of all the analysis summarized in the above information, today I'm taking a risk and publishing, without explanation (it would take pages and pages of text) the grand WJ III CHC+ interpretation scheme that I've iterated to. An image of the grand scheme is below.....simply to catch your attention. You can see a much larger and clearer version of the proposed/hypothesized interpretation system by clicking here (PDF file).

I do hope to explain the logic, rationale, data, hypotheses behind the components of this document over time...maybe through a series of blog posts. To wait until I have written everything will simply keep this baby from being born....and, I am anxious to receive feedback.

I hope it makes sense. Please be sure to read the material I mentioned above as it provides the proper context of this proposed interpretative framework. This framework is offered in the spirit of a hypothesized model that is "under construction" and needs further study with proper methods.

I would suggest channeling any discussion to the CHC listserv.

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IQ Test DNA Fingerprints: Comparison of WJ III/BAT III to WJ-R/BAT-R

Here is another of IQ's Corner "IQ Test CHC DNA Fingerprint" test comparison series.  This particular CHC fingerprint figure compares the CHC composition of the respective full scale total composite IQ scores from the WJ III/BAT III and the the earlier version of these batteries....the WJ-R/BAT-R.

Background information regarding the development, use and interpretation of this IQ global IQ score feature can be found at a prior post and in the IQ Test CHC DNA Fingerprint section on the blog side bar.  More can be found at IQ's Corner sister blog...the ICDP blog.

I now present a comparison of the R/III versions of the WJ/BAT batteries as I have seen psych reports where a subject had previously been administered the WJ-R and was later tested with the revised WJ III (in the case of Spanish-speaking individuals, I've seen the BAT-R and the BAT-III---click here for more background information on the Spanish version of the WJ III...the BAT III).  

In the case of the WJ-R/BAT-R, the full scale IQ composite is called the Broad Cognitive Ability (BCA) cluster.  The name was changed in the WJ III/BAT III to General Intellectual Ability (GIA) cluster.  The name change was not cosmetic.  The use of the term "general intellectual ability" in the newest WJ III/BAT III reflects the fact that this global IQ composite score is designed to be the best statistical estimate of the theoretical construct of general intelligence (g) via the use of differential test weights.

Using principal components analysis, a g-factor was extracted from the seven WJ III/BAT III Standard Cognitive battery tests (at each age level), g-factor weights calculated (by age---they shift slightly as a function of age), and the g-weights used to differentially weight the contribution of the seven tests to the composite GIA-Standard cluster score.  The same process was completed for the 14 test GIA-Extended cluster score.  This procedure is explained in detail in the WJ III/BAT III technical manuals/reports and is also briefly summarized in a free on-line Assessment Service Bulletin technical abstract.

In the case of the WJ-R/BAT-R, the respective 7-test BCA-Standard and 14-test BCA-Extended cluster scores are based on the simple arithmetic average of each set of scores, thus resulting in an equally weighted global IQ score.

Thus, differences between the global WJ-R/BAT-R and WJ III/BAT III IQ scores may occur as a function of the respective scores reflecting differential contributions of the broad Gf-Gc abilities as per the CHC theoretical model that underlies the batteries.

Below is the IQ Test CHC DNA Fingerprint comparison of the two respective editions of the WJ-R/BAT-R and WJ III/BAT III.  The weights presented for the WJ III/BAT III are the median (average) weights across all age groups.  The previously referenced ASB (see above) includes a table of the specific weights by age.

[double click on figure to enlarge]

Although the CHC composition of the respective global IQ scores did not change dramatically, there are enough differences by CHC ability to suggest that slightly different global IQ scores may be produced for the same individual depending on whether they took the WJ-R/BAT-R or the WJ III/BAT III (assuming proper administration, scoring, etc.).  Consistent with psychometric intelligence theory (aka., CHC theory), the WJ III/BAT III global IQ scores (GIA-Stnd; GIA-Ext) are more heavily weighted as per a subjects performance on the more g-loaded measures of Gf (fluid intelligence/reasoning), Gc (crystallized intelligence or comprehension-knowledge), and Glr (long-term storage and retrieval).  In contrast, abilities that are less cognitively demanding and more related to perceptual (Gv, Ga), speed (Gs), and short-term memory (Gsm) functioning contribute slightly less to an individuals WJ III/BAT III global IQ GIA score than was the case with the WJ-R/BAT-R.

If significant differences are found when comparing scores from the respective R/III editions of the WJ for an individual, examiners should review the Gf-Gc CHC test/cluster profiles to determine if some (or all) of the score differences might be related to the shift from an equally weighted global IQ score (WJ-R/BAT-R) to a differentially-weighted (WJ III/BAT III) global IQ score.  In theory, an individual could obtain very similar test-level scores on each battery, but because "all scores are not created equal" (in the estimation of general intelligence or g) in the case of the WJ III, a shift in the global GIA IQ scores may occur.

Other IQ Test CHC DNA Fingerprint comparisons can be found by clicking here.  More will be coming in the future.

[Conflict of interest note:  I am a co-author of the WJ III/BAT III]

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Thursday, October 15, 2009

AP101 Brief #1: g or not to g: IQ part vs full scale IQ scores in determining general intelligence

IQs Corner readers may find the Applied Psychometrics 101 Brief #1:  g or not to g in Atkins MR death penalty cases (post at sister blog) of interest.  Briefly, the two-post AP101 Brief presents and disucsses the relative g-loadings (g-ness) of composite scores from the WAIS-III, WJ III, and KAIT in a university adult sample. Questions are raised, based on analysis of data from a sample of 200 young adults, regarding the use of different composite scores from intelligence batteries in place of the total (full scale) IQ score when considerable variability exists in an IQ batteries composite scores.

Friday, April 03, 2009

WISC-IV cognitive proficiency index

Just learned that the WISC-IV now has a way to provide a "cognitive proficiency" index.  See Technical Report 6.

Interesting.  Composition is conceptually identical to WJ III Cognitive Efficiency cluster (Gsm+Gs), one of the most sensitive clusters for all kinds of deficits and disorders.  Welcome aboard WISC-IV.  Imitation is the best form of flattery [conflict of interest - I'm a coauthor of the WJ III)

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