The use of the Woodcock-Johnson Fourth Edition (WJ IV) GIA Cognitive IQ score in intellectual disability (ID) determination

The WJ IV Cognitive GIA in iintellectual disability (ID) assessment from Kevin McGrew

Law Review Article: Evaluating Intellectual Disability: Clinical Assessments in Atkins Cases (Ellis et al., 2018)

This new law review article is, IMHO, the best overview article regarding the history of ID, the legal issues in Atkins cases, and good discussion of the major conceptual and measurement issues found in many Atkins cases. An excellent introduction to ID issues in Atkins cases.

EVALUATING INTELLECTUAL DISABILITY: CLINICAL ASSESSMENTS IN ATKINS CASES

James W. Ellis, Caroline Everington, Ann M. Delpha

ABSTRACT

The intersection of intellectual disability and the death penalty is now clearly established. Both under the U.S. Supreme Court's constitutional decisions and under the terms of many state statutes, individual defendants who have that disability cannot be sentenced to death or executed. It now falls to trial, appellate, and post-conviction courts to determine which individual criminal defendants are entitled to the law's protection. This Article attempts to assist judges in performing that task. After a brief discussion of the Supreme Court's decisions in Atkins v. Virginia, Hall v. Florida, and Moore v. Texas, it analyzes the component parts and terminology of the clinical definition of intellectual disability. It then offers more detailed discussion of a number of the clinical issues that arise frequently in adjudicating these cases. For each of these issues, the Article's text and the accompanying notes attempt to provide judges with a thorough survey of the relevant clinical literature, and an explanation of the terminology used by clinical professionals. Our purpose is to help those judges to become more knowledgeable consumers of the clinical reports and expert testimony presented to them in individual cases, and to help them reach decisions that are consistent with what the clinical literature reveals about the nature of intellectual disability and best professional practices in the diagnostic process.

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Sixth Circuit Court of Appeals rules (Black v Carpenter, 2017) against norm obsolescence (Flynn effect) adjustment of IQ scores in Atkins death penalty cases

A newly published 6th Circuit opinion (Black v Carpenter, 2017) rules against norm obsolescence (the Flynn effect) in the evaluation of IQ test scores in Atkins ID death penalty cases.  I obviously disagree with this decision as outlined in my 2015 chapter in the AAIDD "The Death Penalty and Intellectual Disability" (Polloway, 2015).

I have no further comment at this time as my expert opinion is clearly articulated in the AAIDD publication and I will continue my efforts to educate the courts.  This decision is at variance with the official positions of American Association on Intellectual and Developmental Disabilities (AAIDD) and the American Psychiatric Association (DSM-5), the two professional associations with official  guidance regarding  the diagnosis of ID. 

This looks like another issue that might need the attention of SCOTUS.

The following section is extracted from the complete ruling.


E. Implications of the Flynn Effect

There is good reason to have pause before retroactively adjusting IQ scores downward to offset the Flynn Effect. As we noted above, see n.1, supra, the Flynn Effect describes the apparent rise in IQ scores generated by a given IQ test as time elapses from the date of that specific test’s standardization. The reported increase is an average of approximately three points per decade, meaning that for an IQ test normed in 1995, an individual who took that test in 1995 and scored 100 would be expected to score 103 on that same test if taken in 2005, and would be expected to score 106 on that same test in 2015. This does not imply that the individual is “gaining intelligence”: after all, if the same individual, in 2015, took an IQ test that was normed in 2015, we would expect him to score 100, and we would consider him to be of the same “average” intelligence that he demonstrated when he scored 100 on the 1995-normed test in 1995. Rather, the Flynn Effect implies that the longer a test has been on the market after initially being normed, the higher (on average) an individual should perform, as compared with how that individual would perform on a more recently normed IQ test.

At first glance, of course, the Flynn Effect is troubling: if scoring 70 on an IQ test in 1995 would have been sufficient to avoid execution, then why shouldn’t a score of 76 on that same test administered in 2015 (which would produce a “Flynn-adjusted” score of 70) likewise suffice to avoid execution? Further, even if IQ tests were routinely restandardized every year or two to reset the mean score to 100, and even if old IQ tests were taken off the market so as to avoid the Flynn Effect “inflation” of scores that is visible when an IQ test continues to be administered long after its initial standardization, that would only mask, but not change, the fact that IQ scores are said to be rising.

Indeed, perhaps the most puzzling aspect of the Flynn Effect is that it is true. As Dr. Tassé states in his declaration, “[t]he so-called ‘Flynn Effect’ is NOT a theory. It is a wellestablished scientific fact that the US population is gaining an average of 3 full-scale IQ points per decade.” The implications of the Flynn Effect over a longer period of time are jarring: consider a cohort of individuals who, in 1917, took an IQ test that was normed in 1917 and received “normal” scores (say, 100, on average). If we could transport that same cohort of individuals to the present day, we would expect their average score today on an IQ test normed in 2017—a century later—to be thirty points lower: 70, making them mentally retarded, on average.

Alternatively, consider a cohort of individuals who, in 2017, took an IQ test that was normed in 2017 and received “normal” scores (of 100, on average). If we could transport that same cohort of individuals to a century ago, we would expect that their average score on a test normed in 1917 would be thirty points higher: 130, making them geniuses, on average.

It thus makes little sense to use Flynn-adjusted IQ scores to determine whether a criminal is sufficiently intellectually disabled to be exempt from the death penalty. After all, if Atkins stands for the proposition that someone with an IQ score of 70 or lower in 2002 (when Atkins was decided) is exempt from the death penalty, then the use of Flynn-adjusted IQ scores would conceivably lead to the conclusion that, within the next few decades, almost no one with borderline or merely below-average IQ scores should be executed, because their scores when adjusted downward to 2002 levels would be below 70. Indeed, the Supreme Court did not amplify just what moral or medical theory led to the highly general language that it used in Atkins when it prohibited the imposition of a death sentence for criminals who are “so impaired as to fall within the range of mentally retarded offenders about whom there is a national consensus,” 536 U.S. at 317. If Atkins had been a 1917 case, the majority of the population now living—if we were to apply downward adjustments to their IQ scores to offset the Flynn Effect from 1917 until now—would be too mentally retarded to be executed; and until the Supreme Court tells us that it is committed to making such downward adjustments, we decline to do so.

* * *

COLE, Chief Judge, concurring in the opinion except for Section II.E. I concur with the majority opinion except as to the section discussing the implications of the Flynn Effect. In holding that Black did not prove that he had significantly subaverage general intellectual functioning, we concluded that Black’s childhood IQ scores would be above 70 even if we adjusted those scores to account for both the SEM and the Flynn Effect. Accordingly, I would not address the question of whether we should apply a Flynn Effect adjustment in cases generally because it is unnecessary to the resolution of Black’s appeal. Regardless, courts, including our own in Black I, have regarded the Flynn Effect as an important consideration in determining who qualifies as intellectually disabled. See, e.g., Black v. Bell, 664 F.3d 81, 95–96 (6th Cir. 2011); Walker v. True, 399 F.3d 315, 322–23 (4th Cir. 2005).

Stephen Greenspan on "Why DSM5 suggested a switch from adaptive behavior to adaptive reasoning": APA Div 33 featured conversation

 

My long time friend and professional colleague Dr. Stephen Greenspan, is conducting a featured conversation hour for Division 33 at the forthcoming APA convention in Denver.  He has provided me an advanced copy of his outline and has graciously given me permission to make it available at the ICDP blog.  A copy can be obtained by clicking here.

Stephen is one of the great "thinkers" in the field of intellectual disabilities.  Our professional lives crossed long distance when I was a doctoral student.  My advisor, Dr. Robert Bruininks, put me in charge of a series of studies investigating the constructs of adaptive and maladaptive behavior.  These studies eventually led to my dissertation--which was a CFA validation study of Greenspan's Model of Personal Competence (see 1990 reference below).  To the best of my knowledge, this was the first published article validating Greenspan's model.

Below are links to the various articles (I simply grabbed them from my MindHub web page--please visit if you want additional information).  Consistent with Stephen's outline notes, in this validated model of personal competence, conceptual intelligence was operationalized as measured by intelligence tests, and was not considered a domain of adaptive behavior.

Of interest is the recent study by MaCann et al. that provides structural (CFA) evidence for a separate cognitively oriented social-emotional construct, distinct from the other cognitive domains in the CHC taxonomy of human intelligence.  Although MaCann et al. refer to the construct as emotional intelligence, a reading of the dimensions suggest it could easily be called social intelligence.  

Finally, as Bruininks and I were pulled away from our AB/PC program of research for different reasons, I continue to be perplexed why other researchers have not tried to extend and refine the research on the model of personal competence, particularly given its prominence (and disagreements) in definitions of ID.

Adaptive Behavior and Personal Competence Research (select articles)

• Thompson, J. R., McGrew, K. S., & Bruininks, R. H. (2002).  Pieces of the puzzle. Measuring the personal competence and support needs of persons with intellectual disabilities. Peabody Journal of Education, 77(2), 23-29.
• Thompson, J., McGrew, K. & Bruininks, R. (1999).  Adaptive and maladaptive behavior.  Functional and structural characteristics.  In R. L. Schalock & D Braddock (Eds), Adaptive behavior and its measurement: Implications for the field of mental retardation(pp. 15-42).  Washington, DC.  American Association on Mental Retardation.
• Widaman, K. & McGrew K., (1996).  The structure of adaptive behavior.  In J.W. Jacobson & J.A. Mulick (Eds.), Manual of diagnosis and professional practice in mental retardation (pp. 97-110).  Washington, D.C.  American Psychological Association.
• McGrew, K., Bruininks, R., & Johnson, D. (1997).  Confirmatory factor analysis investigation of Greenspan's model of personal competence.  American Journal on Mental Retardation, 100(5) 533-545.
• Greenspan, S., & McGrew, K. (1996).  Response to Mathias and Nettlebeck on the structure of competence.  Need for theory-based methods to test theory-based questions.  Research in Developmental Disabilities, 17, 145-152.
• Bruininks, R., Chen, T., Lakin, C., & McGrew, K. (1992).  Components of personal competence and community integration for persons with mental retardation in small residential programs. Research in Developmental Disabilities, 13, 463-479.
• Ittenbach, R., Spiegel, A., McGrew, K., & Bruininks, R.  (1992). A confirmatory factor analysis of early childhood ability measures within a model of personal competence.  Journal of School Psychology, 30, 307-323.
• McGrew, K., Bruininks, R., & Thurlow, M. (1992). Relationship between measures of adaptive functioning and community adjustment for adults with mental retardation. Exceptional Children, 58, 517-529.
• McGrew, K., Ittenbach, R., Bruininks, R., & Hill, B. (1991). Factor structure of maladaptive behavior across the lifespan for persons with mental retardation. Research in Developmental Disabilities, 12, 181-199.
• McGrew, K., & Bruininks, R. (1990).  Defining adaptive and maladaptive behavior within a model of personal competence. School Psychology Review, 19, 53-73.
• McGrew, K., & Bruininks, R. (1989).  The factor structure of adaptive behavior. School Psychology Review, l8, 64-8l.
• Bruininks, R., McGrew, K., & Maruyama, G. (1988).  Structure of adaptive behavior in samples with and without mental retardation.  American Journal on Mental Retardation, 95(3), 265-272.

Comments on Proposed DSM-5 SLD Criteria: Colker, Shaywitz, Shaywitz & Simon

A copy of the following paper found its way to my inbox over the 4th of July holiday. It is written by Colker, Shaywitz, Shaywitz & Simon.

Comments on Proposed DSM-5 Criteria for Specific Learning Disorder from a Legal and Medical/Scientific Perspective



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www.themindhub.com

Coalition for DSM-5 reform call for independent reviews and letters

The Coalition for DSM-5 has announced an open letter campaign to solicit independent reviews and feedback regarding DSM-5. - Posted using BlogPress from Kevin McGrew's iPad

Reading fluency and reading LD/dyslexia: Guest post by John DeMann

The following is a guest blog post (previously called virtual scholars at this blog)  by John J. DeMann, NCSP, School Psychologist, North Allegheny School District.  John took advantage of my standing offer to readers of my blogs to receive a PDF copy of any article I mention in a research brief (or byte ) or any article that may be in a recent "IQs Corner Recent Literature of Interest" post.  I know that many practitioners do not have access to journals......so if a person volunteers to make a brief written post, I'm willing to send them a PDF copy of the article in exchange for the post.

This feature benefits all readers as the post is "added value and commentary" which then allows me to provide a link to the full article (via the "fair use doctrine"---esp. for educational purposes) for all to read.  So it is a win-win and "help your colleagues" type of exchange program.

John's post is very well written and provides a nice overview of the article along with some stimulating ideas and thoughts.  Thanks John.  His post is reproduced below "as is" (save any minor copy edits and or the adding or URL links by the blogmaster).  If you are considering a guest post, don't think your post has to be as long as John's.  Individual differences in guest posting is valued and recognized.

Recently, increased interest in reading fluency has emerged in both the professional literature and in applied practice. Oral reading fluency is typically the outcome variable by which response to intervention (RTI) models are evaluated, and is usually measured by a child's rate and accuracy (words correct/minute) when reading connected text. With the ubiquity of interventions targeting core phonological awareness deficits, attention has shifted to other cognitive variables that influence reading development beyond single-word reading and decoding difficulties. Although traditional assessment and definitions of dyslexia focus on single-word reading and decoding deficits, difficulty with reading fluency has been increasingly recognized as an important characteristic of dyslexics. For example, the recent reauthorization of the Individuals with Disability Education Improvement Act (IDEA, 2004) now recognizes reading fluency as one of the eight areas of specific learning disability. More recent conceptualizations of the term dyslexia also include references to fluency as an area of difficulty experiences by individuals with dyslexia. Further, the authors of the forthcoming revision to the Diagnostic and Statistical Manual of Mental Disorders (5th edition) are proposing a revised definition of dyslexia that includes difficulties in accuracy or fluency. This increased attention to fluency as an important aspect of reading may be the result of fluency being recognized as an important contributor to the overall goal of reading - comprehension. Reading fluency is essential for a child's academic success, as dysfluent reading is likely to significantly interfere with reading comprehension and thereby hamper the learning of content area knowledge. Although intervention research has established reading fluency's importance in developing overall reading skills, more work is needed to explore dyslexia characterized primarily by a lack of fluency and gain consensus regarding disability subtypes and cognitive components of fluency.

Meisinger et al.'s article, Reading Fluency: implications for the assessment of children with reading disabilities (Annals of Dyslexia, 2010, 60, 1-17) establishes an argument for the importance of fluency as an overall indicator of reading ability, and stresses the importance of including standardized measures of fluency when conducting comprehensive assessments. In the current age of formative assessment and response-to-treatment models dominating the school psychology landscape, these authors argue that reliable and valid measures of fluency may be an overlooked aspect of assessment given the shortcomings of many assessment instruments. They argue that many common assessment instruments that measure reading skills include measures of word reading, decoding, and comprehension, but seldom include measures of reading fluency. Additionally, they point-out the inconsistency of how reading fluency is defined by various tests. For example, the Reading Fluency subtest from the Woodcock-Johnson Tests of Achievement - Third Edition (WJ-III ACH) measures an individual's ability to quickly read simple statements and decide whether they are accurate (i.e. includes comprehension), whereas other measures characterize fluency as an individual's ability quickly and accurately read larger blocks of text (e.g. GORT-4). Regardless of how fluency is measured, Meisinger et al. caution that the omission of fluency in the assessment of an individual's reading skills may have important implications for diagnostic decision making. They reference recent research that suggests word reading and reading fluency are distinct skills that each make unique contributions to an individuals reading comprehension. Therefore, evaluations that do not include measures of reading fluency may lead to erroneous or misleading conclusions regarding an individual's reading abilities.

As a result of this significant problem, Meisinger et al. chose to examine the diagnostic utility of reading fluency to identify children with reading disabilities by (a) determining whether there are children who have typically developing word identification and decoding skills but show specific deficits in reading fluency; (b) examine which cognitive features differentiate children with specific reading fluency deficits from struggling and normal readers, and (c) investigating whether the omission of reading fluency in the assessment of children would results in the under-identification of children with reading disabilities. The results of their study suggest:

* reading fluency measures are more sensitive in detecting reading problems than word reading measures

* it is essential to evaluate reading fluency when assessing children referred for reading difficulties; failure to do so may result in the under-identification of children with reading disabilities

* results support the identification of a subgroup of children who exhibit specific deficits in reading fluency without concordant deficits in single word reading in isolation or in decoding unknown words ("double-deficit" reading disability subtypes

* RAN is an underlying process that plays an important role in determining the rate at which children read connected text

* compared to children with normal reading skills, children with deficits in reading fluency were characterized by deficits in rapid naming speed but not in phonological processing

These results, as the authors suggest, have important implications for practitioners, suggesting that psycho-educational assessment that does not include measures of reading fluency is at risk of under-identifying children who would otherwise be classified as reading-disabled. These results also support the need for increased focus on intervention that leads to improved reading skills beyond the single-word level.

In review of this article, a few criticisms/caveats to consider: the authors indicate that a comprehensive, standardized test that measures word reading, decoding, fluency, and comprehension does not exist, making a cross-battery approach necessary to measure all variables in this study. Therefore, as the authors suggest, differences in test characteristics could account for the observed differences in performance on these measures. Although the WJ-III measures all aspects of reading used in their study, they chose to use a measure of fluency that aligns with more current definitions (e.g. National Reading Panel). It might be interesting to see how these tests choose to conceptualize fluency in future test revisions. The new WIAT-III (which wasn't released until after this study was submitted for review) defines fluency much like the GORT-4, and benefits from being a comprehensive, co-normed battery. A replication of this study using the WIAT-III norming sample could mitigate the sampling and testing error differences reported in this study, and determine whether these results generalize to a larger normative sample - the sample used in this study was selected from a largely white, clinic-referred sample of children previously diagnosed with a reading disability or suspected of having reading problems. Lastly, the authors suggest that their results should be replicated and expanded upon by exploring other potentially important variables that may contribute to reading fluency performance. For example, working memory is offered as another potentially important cognitive variable for reading fluency that could be included in this model to predict variance in reading fluency performance. Despite the evidence that demonstrates RAN is an underlying process that plays an important role in identifying reading difficulties, our understanding of why children with reading problems display these deficits is still limited. From a CHC perspective, RAN tasks share both cognitive speediness (Gs) and naming/retrieval (Glr) performance aspects; another question that remains as a result of this study is whether RAN deficits represent a more general slow speed of processing (Gs), or whether RAN deficits are related to slowness specific to letters/numbers that hampers the development of fluent reading.

It is apparent that reading fluency represents a largely under-studied area of reading research that may be a key area of assessment for children who experience reading problems. Most importantly, assessment practices that include standardized fluency measures may help differentiate intervention for students who experience difficulty developing fluency beyond word-identification skills.

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AAIDD position paper on DSM-V proposed definition of intellectual disability (ID)

Yesterday AAIDD presented its formal reaction to the DSM-V ASD and Developmental Disorders Subgroup, ID Subcommittee regarding the proposed DSM-V definition for intellectual disability (ID). The AAIDD 11th Edition Implementation Committee position paper (and recommendations) can be found by clicking here.


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Critque of proposed DSM5 intellectual disability criteria: Guest post by Dr. Dale Watson

Without question, the DSM-5 Proposed Draft Revision document has been generating considerable chatter among psychologists.  With regard to Atkins cases, the proposed definition of intellectual disability (ID) is no exception....emails and listservs have been busy debating and critiquing the ID proposed criteria. 

Dr. Dale Watson has set out a well-written set of concerns and issues in the guest blog post below---which is reproduced "as is" from Dr. Watson.  Kudos to Dale for providing ICDP with his perspective.

Dr. Dale Watson's critique of the proposed DSM-V ID criteria follows:

The DSM-5 Proposed Draft Revisions to the Criterion sets for Mental Disorders have recently become available.  The proposed criteria for the diagnosis of Intellectual Disability retain the three-pronged model of diagnosis used by both the DSM-IV and the AAIDD.  However, the revised language, though more precise in some ways, is also potentially problematic for a number of reasons and requires further clarification.  The following critique outlines concerns regarding the revised language and is a request for further clarification and/or specificity in the diagnostic language.

The first prong of the revision appears initially to improve the specificity of the IQ requirements stating, “Current intellectual deficits of two or more standard deviations below the population mean, which generally translates into performance in the lowest 3% of a person’s age and cultural group, or an IQ of 70 or below.”  Certainly using “standard deviations below the population mean” adds a degree of precision and perhaps allows for consideration of “Flynn Effect” changes in the population mean.  However, in an Atkins context, this language also appears to foreclose sole reliance on historical test scores in establishing the diagnosis in that it requires “current intellectual deficits.”  In addition, by eliminating the DSM-IV “IQ of approximately 70 or below” there must be some concern that this proposal establishes a “bright-line” cutoff of “70 or below” for the diagnosis of an Intellectual Disability.  Despite the rationale provided by the Work Group that the proposed criteria add “rigor to wording regarding psychometrics [with] (no change in cut –off)” one must be concerned that this is, in effect, a change in the cutoff.  In justifying the changes in the coding procedure, the rationale indicates, “Inaccuracy of testing no longer a factor.”  Does this mean that eliminating the word “approximately,” as used in DSM-IV and by the AAIDD, also eliminates consideration of the Standard Error of Measurement?  Does this mean, as is the practice in a number of death-penalty states, that it is no longer “possible to diagnose Mental Retardation with IQ scores between 71 and 75…”  (DSM-IV, p. 48).  If that were the case, the proposed criteria would not be consistent with clinical practice nor would it, by ignoring the standard error or measurement, be “adding [psychometric] rigor.”

The revision language also acknowledges the importance of cultural sensitivity, which, on the face of it, should not be objectionable.  However, by stating that the IQ requirement “translates into performance in the lowest 3% of a person’s age and cultural group…” there is a risk that this will be used as a rationale to establish subgroup norms rather than relying, as indicated, on the “population mean.”  Certainly we have seen attempts by some psychologists to use membership in a presumed cultural group to inflate IQ scores thus making legitimately intellectually disabled individuals eligible for the death penalty.  These attempts have included the use of Heaton’s WAIS-III demographically adjusted norms and what have been termed “IQ-Quality” scores, both of which inflate the obtained IQ scores based upon subgroup membership to establish that individuals do not have an Intellectual Disability.  IQs, by definition, must reference population rather than subgroup standards.

There is also either ambiguity or a substantially increased demand for deficits in adaptive function, in the proposed language for the second prong of the diagnosis.  The proposed criteria require:

 [C]oncurrent deficits in at least two domains of adaptive functioning of at least two or more standard deviations, which generally translates into performance in the lowest 3 % of a person’s age and cultural group, or standard scores of 70 or below.  This should be measured with individualized, standardized, culturally appropriate, psychometrically sound measures.  Adaptive behavior domains typically include:

• Conceptual skills (communication, language, time, money, academic)
• Social skills (interpersonal skills, social responsibility, recreation, friendships)
• Practical skills (daily living skills, work, travel).
  

The ambiguity arises when one considers what is meant by a “domain.”  DSM-IV required deficits in at least two “areas” (similar to what appear to be sub-domains above).  In contrast, AAIDD has rightfully relied upon, based on factor analytic studies and the work of Stephen Greenspan, deficits in the domains of Conceptual, Social and Practical skills.  However, the AAIDD requires adaptive function deficits in only one as opposed to two domains.  The current AAIDD manual operationally defines significant limitations in adaptive behavior as “performance that is approximately two standard deviations below the mean of either (a) one of the following three types of adaptive behavior: conceptual, social, or practical or (b) an overall score on a standardized measure of conceptual, social, or practical skills.  The assessment instrument’s standard error of measurement must be considered when interpreting the individual’s obtained scores” p. 43.  The impact of requiring deficits in two of the three domains, as apparently required by the proposed criteria, has long been recognized.  For example, The 2002 AAMR Mental Retardation: Definition, Classification, and Systems of Supports manual described the impact that requiring deficits in two or more of the three domains would have on the prevalence of intellectual disabilities:

…the probability of a person having significant deficits (2 SDs below the mean) in two or in all three domains of adaptive behavior is extremely low compared to the probability of scoring two standard deviations or below on only one domain.  In fact, simulation studies have demonstrated that the probability of a person scoring two standard deviations below the mean on more than one domain would be so low that almost no one with an IQ in the upper mental retardation range would be identified as having mental retardation (K.F. Widaman, personal communication, November 9, 2001) (p. 78).

The proposed DSM-5 language, rather than having “Consistency with AAIDD practices,” as stated in the rationale, appears to fly in the face of those standards and would insure that “almost no one with an IQ in the upper mental retardation range would be identified as having” an intellectual disability.  In addition, by failing to note the importance of considering the “instrument’s standard error of measurement” the proposed criteria once again suggests a “bright-line” cut-off for both the intellectual and adaptive functioning requirements.  Effectively, and contrary to the stated rationale, these proposals represent changes in the cutoff scores.  In an attempt to establish unambiguous criteria for the intellectual and adaptive behavior diagnostic prongs the proposed language ignores a fundamental understanding of the nature of test scores, i.e., that some degree of imprecision is inherent.

The practical impact of these proposed criteria within a clinical context would be to reduce the number of individuals diagnosed with an Intellectual Disability.  Within an Atkins context, these changes would make more individuals eligible for the death penalty.

The Work Groups for DSM-5 are soliciting comments upon the proposed diagnostic criteria until April 20, 1010 at www.dsm5.org.  I would urge anyone with concerns regarding the criteria to submit their comments.

Dale G. Watson, Ph.D.
Clinical and Forensic Neuropsychologist
watson.dale@comcast.net

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DSM-5: Proposed draft revisions: Intellectual Disability

The Proposed Draft Revisions to DSM-5 are now available on line.  MR/ID is described as the following:

Intellectual Disability

A. Current intellectual deficits of two or more standard deviations below the population mean, which generally translates into performance in the lowest 3% of a person's age and cultural group, or an IQ of 70 or below. This should be measured with an individualized, standardized, culturally appropriate, psychometrically sound measure.

B. And concurrent deficits in at least two domains of adaptive functioning of at least two or more standard deviations, which generally translates into performance in the lowest 3 % of a person's age and cultural group, or standard scores of 70 or below. This should be measured with individualized, standardized, culturally appropriate, psychometrically sound measures. Adaptive behavior domains typically include:

• Conceptual skills (communication, language, time, money, academic)
• Social skills (interpersonal skills, social responsibility, recreation, friendships)
• Practical skills (daily living skills, work, travel)

C. With onset during the developmental period.

Code no longer based on IQ level.

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