Thursday, April 21, 2005

Clarification of value of IQ tests in education: Response to the Reid Lyon DC gang

It has come to my attention that a report I previously directed blog readers to (Expectations for Students with Cognitive Disabilities: Is the Cup Half Empty or Half Full? Can the Cup Flow Over?) (IQ Scores, Forest Gump & NCLB: Run Forrest..Run), has made it to high places....which is not always good....especially when these places are awash in a sea of politics.

Briefly, in the recent announcement from the U.S. Department of Education that there should be an increase in the percent of students with disabilities who can be excluded from state NCLB-related assessments, (Raising Achievement: Alternative Assessment for Students with Disabilities), yours truly (and, indirectly, my associate Jeff Evans), is cited in support of, what can only be called, and anti-intelligence testing position in special education. As a coauthor of the Woodcock-Johnson III battery, which includes a comprehensive CHC-based intelligence battery, the attribution of an anti-IQ position to me may strike readers as bizarre, and, if believed, possibly suggestive of myself experiencing a break from reality.

Below is the select quote (emphasis added by me) from the ED.gov web URL cited above:
  • "Research also supports the idea that IQ does not dictate achievement and, thus, cannot be used as a predictor. Kevin McGrew of the Institute for Applied Psychometrics notes that for most children with below average IQ scores, it is not possible to predict expected achievement with much accuracy. Lower-than-average IQ does not automatically translate into lower achievement or less ability to learn reading, language arts, mathematics, or other subjects. Other important variables affecting achievement appear to be interpersonal skills, motivation, engagement, and study skills, all of which can be positively influenced by high standards and expectations. Unfortunately, students are too often given a curriculum that is driven by educators' expectations of their students (based in part on a misunderstanding of IQ).
First, the later half of this statement is 100% true. As I've written elsewhere, non-cognitive factors (e.g., conative variables - motivation, self-regulated learning strategies, social and interpersonal abilities, etc.) are often ignored when making statements about a student's "aptitude" for school learning. I'm a firm believer in the Richard Snow approach to defining school aptitude as a combination of both cognitive and conative abilities. Nowhere have I ever written that valid measures of theory-based intelligence tests are not useful or predictive. In fact, I've authored/coauthored four different books on the interpretation of intelligence batteries. In the report drawn upon, I simply describe the normal curve of achievement scores that surround any specific IQ score, and this variability makes it difficult to predict, with precise accuracy, the exact level of expected current or future achievement for a specific student.

What I did write, and which is misconstrued in the ED.gov announcement, is the honest truth about our best measures of cognitive abilities. Namely, they are fallible predictors. Intelligence tests do not, nor have they ever, nor will they likely ever, account for school achievement beyond a threshold of approximately 40-60% of academic achievement variance....which is a hell of a lot in the field of psychology!

Cognitive measures, as per all respected models of school learning (e.g., Carroll's Model of School Learning; Walberg's Model of Educational Productivity), all include student characteristics, and cognitive characteristics in particular, as important contributing/predictive variables in explaining school learning. The point made in the Forrest Gump report is that even today's best available intelligence batteries are fallible predictors that do not allow educators to predict, beyond a reasonable doubt, specific expected levels of current or future achievement without a known degree of error. But, this degree of uncertainty (or error of prediction) is known and can be quantified. When combined with other variables (e.g., conative characteristics; home environment variables; quantity and quality of instruction), intelligence tests can provide valuable explanatory and predictive information.

The anti-IQ rhetoric coming out of many politically correct academic school psychologist channels, as well as the powers-that-be driving the special education reforms at the federal level, is accurate in the statement that global/full-scale IQ scores, and their use in ability-achievement formula's for LD determination, is not an empirically-based defensible procedure. I couldn't agree more.

However, cognitive measures, especially those that are based on contemporary psychometric theory (e.g., CHC theory), and those that provide reliable and construct valid measures of most of the major broad CHC ability domains, can, and do provide useful information in the hands of skilled clinicians. In fact, those advocating against IQ tests offer, as alternatives, measures or "markers" of phonemic awareness, rapid automatized naming, working memory, and vocabulary to identify students at risk for reading disabilities. Anyone with any knowledge of CHC theory recognizes that these marker/screening abilities can be directly mapped to the CHC abilities of phonetic coding (Ga-PC), naming facility (Glr-NA), working memory (Gsm-MW), and lexical knowledge (Gc-VL). AND, all of these abilities are measured on the most comprehensive CHC-based intelligence batteries. Isn't the addage "don't throw the baby out with the bathwater" applicable?

The real irony (in the misrepresentation of the information in the Forrest Gump report) in the U. S. Dept. Of Education statement, is that the primary premise of the report was that students with disabilities should not be denied high expectations, inclusion in state assessments, or access to the general education curriculum based only on a single point IQ score. The primary theme of the report was that, for too long, some educators, psychologists, and policy makers have believed in the supreme power of IQ tests, to the point that inappropriately low academic achievement expectations may be formed. Furthermore, the primary thesis of that report is that kids with disabilities (that are so classified based on intelligence test scores) should be NOT be automatically excluded from high standards and state accountability systems--the exact opposite message that the ED.gov statement uses our report to support (viz., increasing the percent of students with disabilities in NCLB accountability activities).

Whatever happened to President Bush's statement, when unveiling NCLB, that for too long, many children have been victims of "the soft bigotry of low expectations." Isn't the exclusion of more students with disabilities from high-stakes state accountability systems, systems that require schools to raise their expectations for students, promoting the same "soft bigotry of low expectations?"

As I've often said, and I don't know who to attribute the original quote to (I want to say Ralph Reiten of the Halstead-Reitan Neurospcyhological Battery fame), "if you give a monkey a Stradivarius violin and you get bad music, you don't blame the violin." By extension, if you give a "politically motivated federal bureaucrat honest scholarly information....... [never mind, you get the point].

1 comment:

Anonymous said...

"You can't blame a fever on the thermometer."

-Arthur Jensen