Dr. Judd states:
This case raises a host of issues. In this comment I would like to mention several and then discuss one, measuring adaptive behavior, in more depth.
1. Should U.S. norms for IQ and/or adaptive behavior be used since that is the population they are being judged against and the context of the Atkins decision? Or should we use national norms from the nation of origin or some other subpopulation norms? Or national norms for childhood and U.S. norms for current?
2. MR is not necessarily lifelong. Which time period is relevant? Childhood is relevant by definition. Time of the crime? Time of trial? Time of execution? (The reasoning behind various Atkins decisions suggests to me that all 4 of these time periods are pertinent, so perhaps Atkins evaluations should address all 4 distinctly.)
3. Clinically measuring adaptive behavior in prison and using prison guards is problematic and prone to misinterpretation by the court but should not be entirely ruled out, since such behavior can be pertinent. Just by way of example, if a defendant earned a college degree while in prison it would not be intellectually honest to say that that was irrelevant.
4. Potential bias in rating adaptive behavior (whether by self, family members, friends, teachers, prison guards, etc.) is problematic not only for Atkins but also when mitigation or access to services and disability accommodations and payments may be at stake. For this reason, validity scales in future versions of adaptive behavior scales would be useful. How to devise such scales is tricky, but I have some suggestions to offer here:
a. Items that are very similar to one another could be included and compared for consistency of response, as is done in the PAI, BRIEF and others. This would address accuracy of comprehension, etc. but not systematic bias.
b. Instead of presenting items in order of increasing difficulty by category, as the ABAS and Vineland do, they could be mixed, as in most personality inventories. Then a computer analysis may be able to discriminate if responses regarding the easy versus hard activities show consistency. I believe that a similar strategy is used in the VIP malingering test.
c. The rating scale could be linked to a performance scale concerning selected items on the rating scale. For example, there might be an item, “Is able to read a telephone number of 10 digits and dial it accurately.” This ability could then be tested directly. A few such measures might be unobtrusive, such as filling out their name and address and other information on the rating form and following certain written directions on the form. Norms could be developed regarding how closely performance matches rating and significant deviations might suggest invalid ratings. While an individual might still malinger on both rating and performance, they might not do so consistently. Such a matching could potentially pick up both overly negative and overly positive rating sets and may be particularly useful with respect to the validity of informant ratings.
d. With respect to cultural bias, peer comparisons might be used instead of more absolute ability norms. In other words, items might be constructed as follows: “Compared to others his/her age, his/her ability to ____________ is: Much better, somewhat better, about the same (or average), somewhat worse, much worse.” A similar approach has been used with the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) in which the person rated is compared to themselves 10 years earlier on various everyday memory and executive abilities. The IQCODE has been found to be sensitive to dementia and insensitive to effects of culture and education.
Tedd Judd, PhD, ABPP-CN
Technorati Tags: psychology, forensic psychology, forensic psychiatry, neuropsychology, intelligence, school psychology, psychometrics, educational psychology, IQ, IQ tests, IQ scores, adaptive behavior, adaptive functioning, intellectual disability, mental retardation, MR, ID, criminal psychology, criminal defense, criminal justice, ABA, Atkins cases, Atkins death penalty, American Bar Association, Atkins cases, death penalty, capital punishment, AAIDD, Atkins MR/ID listserv, ICDP blog, psychiatry, psychiatry and criminal justice, Arbeleaz v Florida, cultural issues, cultural sensitivity