© Robert D. Smith, PhD
CRITICAL INFORMATION ABOUT TESTING FOR:DYSLEXIA, LEARNING DISABILITIES AND ADHD If you have had prior tests and were told you did not have dyslexia, learning disabilities, ADHD or ADD, yet you suspect you do have one of these conditions, you may find it beneficial to have a diagnostic interview and have your test results reviewed. A diagnostic interview can be arranged with Dr. Smith through the Michigan Dyslexia Institute. Problems with IQ Testing: Traditionally, the principal method of diagnosing learning disabilities, such as dyslexia, has been to compare measured intelligence and achievement level such as reading. It is expected that the reading score for instance, will be significantly below the IQ score if dyslexia is present. Other factors are also considered, but he center piece to diagnosis is this discrepancy in scores. However, there are serious problems with this approach that are frequently not considered in a diagnostic evaluation. First, the concept of intelligence being a single ability accurately represented by a single score such as IQ has been seriously challenged by research. The overall functioning that is represented by IQ is actually the result of at least four, (and possibly more) separate cognitive abilities. The are most commonly identified as verbal reasoning, nonverbal reasoning, working memory and processing speed. When these are all functioning at the same level, then a single score such as the IQ can be regarded as validly representing a person's intelligence. However, It is not uncommon for people with learning disabilities to have very uneven functioning in these four areas, perhaps ranging from very low to very high. Consequently, a child or adult's reasoning and learning abilities may be much higher than what is reflected in the IQ score. Unfortunately, it is the lower IQ score that is often used in calculating the discrepancy between ability and achievement such as reading resulting in a discrepancy that is deemed within normal limits. Consequently, the learning disability that is actually present is not detected. Failing to detect a problem that is actually present is called a false negative. There are additional consequences in not properly interpreting intelligence tests. Working memory and processing speed are considered aspects of attention and are closely associated with some type of attention deficit disorder. Impairments in these areas strongly suggests that an evaluation for ADHD or ADD is in order. Relying on the traditional IQ score may mask actual impairments and result in failure to detect a problem, when in fact a problem is present. Again a false negative. This can also result in serious under measurement of actual ability or potential. Unfortunately many psychologists are only trained to use the traditional IQ score and ignore indications that a traditional IQ score is invalid. Problems with Testing of Reading: Automaticity is acquired in the latter stage of reading acquisition when decoding of words is automatic and therefore rapid, which allows more mental resources to be directed to the task of reading comprehension. Automaticity is necessary for practical reading typical non-dyslexic readers. However, the extra steps and mental effort the dyslexic reader must use to perform basic decoding continues to reflect the ongoing interference that their dyslexia has with practical reading. Most reading tests that are used to evaluate for dyslexia are untimed and do not require Automaticity of decoding and will often fail to detect the presence of dyslexia in a person who has had substantial remediation. People with dyslexia who have had substantial amount of remedial reading instruction can often perform well on these untimed tests. Consequently, it is important to administer reading tests that require Automaticity of decoding for the evaluation to have a reasonable chance of detecting dyslexia. Unfortunately, such tests are often not included in an evaluation, which may result in a false negative diagnostic conclusion.Problems with ADHD or ADD testing: There is considerable controversy at the present time over what are the core symptoms of ADHD or ADD. ADD, which is ADHD, Predominantly Inattentive Type, is particularly difficult to diagnose because hyperactivity or impulsiveness are not the primary symptoms. People with ADD are not disruptive and are often well behaved in classrooms. Their symptoms involve internal, silent problems of mental processing of information that results in poor academic performance. Because their symptoms are not readily noticed by observers, their condition often goes undetected despite the suspicion that something is just not right. Because of the controversy regarding the core symptoms and the difficulty detecting symptoms evaluations often result in false negatives when in fact there is a problem. Evaluations require a care review of all tests, history, grade reports, teacher reports and parent reports. Click on a Links below to: Contact Dr. Smith Michigan Dyslexia Institute
Robert D. Smith, PhD Diagnosis of Dyslexia, ADD & Learning Disorders Children & Adults