IQ Subtest Scores Research Articles

Behavior patterns in Duchenne muscular dystrophy: Report on the Parent Project Muscular Dystrophy behavior workshop 8–9 of December 2006, Philadelphia, USA

Eighteen participants representing clinicians, scientists, parents, industry, and public health agencies involved in the assessment and treatment of children with Duchenne muscular dystrophy (DMD) from Australia, Canada, the Netherlands, the UK and the USA met in Philadelphia on December 8–9, 2006 to attend a workshop addressing behavioral issues among children and young adults with DMD. The workshop, sponsored by Parent Project Muscular Dystrophy (PPMD–USA), was organized in response to parent and clinician concerns regarding behavior associated with DMD, and its subsequent impact on patient and family quality of life. For the purposes of clarification, in this report the term ‘‘behavior’’ is defined as readily observable external actions and responses, as well as internal affective/emotional states. The aims of the workshop were to (1) evaluate current findings and determine whether characteristic behaviors occur among boys and young men with DMD, (2) examine etiological factors contributing to behavior patterns in DMD, and (3) develop recommendations for research and intervention strategies. DMD is a genetic disorder occurring in approximately one in 3300 live male births. Mutations in the dystrophin gene result in an absence of dystrophin or a non-functional dystrophin protein. The different types and locations of the mutation are highly variable across individuals, and it is

A genetic investigation of the covariation among inspection time, choice reaction time, and IQ subtest scores.

Information processing speed, as measured by elementary cognitive tasks, is correlated with higher order cognitive ability so that increased speed relates to improved cognitive performance. The question of whether the genetic variation in Inspection Time (IT) and Choice Reaction Time (CRT) is associated with IQ through a unitary factor was addressed in this multivariate genetic study of IT, CRT, and IQ subtest scores. The sample included 184 MZ and 206 DZ twin pairs with a mean age of 16.2 years (range 15-18 years). They were administered a visual (pi-figure) IT task, a two-choice RT task, five computerized subtests of the Multidimensional Aptitude Battery, and the digit symbol substitution subtest from the WAIS-R. The data supported a factor model comprising a general, three group (verbal ability, visuospatial ability, broad speediness), and specific genetic factor structure, a shared environmental factor influencing all tests but IT, plus unique environmental factors that were largely specific to individual measures. The general genetic factor displayed factor loadings ranging between 0.35 and 0.66 for the IQ subtests, with IT and CRT loadings of -0.47 and -0.24, respectively. Results indicate that a unitary factor is insufficient to describe the entire relationship between cognitive speed measures and all IQ subtests, with independent genetic effects explaining further covariation between processing speed (especially CRT) and Digit Symbol.

Survivors of neonatal extracorporeal membrane oxygenation at school age: unusual findings on intelligence testing.

Data are presented on 17 children who received extracorporeal membrane oxygenation (ECMO) in the neonatal period for persistent pulmonary hypertension (PPHN). These children are being followed as part of a larger program of follow-up research on children who have been treated for PPHN with several treatment methods. On intelligence testing at ages 5 to 8 years, these 17 children had unusual patterns of results. A higher-than-predicted percentage of the ECMO survivors had discrepancies between their Verbal and Performance IQ and a much-higher-than-predicted percentage had areas of unusual strength or weakness on their IQ subtest scores. Also, there was a significant correlation between the amount of time a child received ECMO and the child's Performance IQ: the longer the child received ECMO, the higher the Performance IQ. While findings of unusual weaknesses or deficits on intelligence testing at school age in children who have been severely ill in the neonatal period are not unusual, findings of high scores and areas of strength are not easily explained, particularly when these findings seem to relate to an invasive treatment like ECMO. Similar findings have been reported in two other small studies, which suggest that the impact of ECMO on the developing infant brain may not be purely detrimental.

Survivors of neonatal extracorporeal membrane oxygenation at school age: unusual findings on intelligence testing

Data are presented on 17 children who received extracorporeal membrane oxygenation (ECMO) in the neonatal period for persistent pulmonary hypertension (PPHN). These children are being followed as part of a larger program of follow‐up research on children who have been treated for PPHN with several treatment methods. On intelligence testing at ages 5 to 8 years, these 17 children had unusual patterns of results. A higher‐than‐predicted percentage of the ECMO survivors had discrepancies between their Verbal and Performance IQ and a much‐higher‐than‐predicted percentage had areas of unusual strength or weakness on their IQ subtest scores. Also, there was a significant correlation between the amount of time a child received ECMO and the child's Performance IQ: the longer the child received ECMO, the higher the Performance IQ. While findings of unusual weaknesses or deficits on intelligence testing at school age in children who have been severely ill in the neonatal period are not unusual, findings of high scores and areas of strength are not easily explained, particularly when these findings seem to relate to an invasive treatment like ECMO. Similar findings have been reported in two other small studies, which suggest that the impact of ECMO on the developing infant brain may not be purely detrimental.

Psychoeducational profile of the 22q11.2 microdeletion: A complex pattern

Objectives: To examine the psychoeducational profile associated with the chromosome 22q11.2 microdeletion (DiGeorge/velocardiofacial syndrome). Study design: Thirty-three patients (aged 6 to 27 years) with a 22q11.2 microdeletion underwent psychoeducational testing as part of a comprehensive evaluation. Nonparametric statistics were used to compare verbal and performance IQ, academic achievement scores, and receptive versus expressive language scores. Post hoc comparisons were made of IQ subtest scores and of language versus verbal IQ. Results: Full-scale IQ ranged from the normal to the moderately retarded range. Mean verbal IQ was significantly higher than mean performance IQ. In a similar manner, mean reading and spelling scores were superior to the mean mathematics score, although achievement scores typically were in the range of verbal IQ. In addition, many children showed clinically significant language impairments, with mean language scores lower than mean verbal IQ. Conclusions: The IQ and academic profiles are reminiscent of a “nonverbal learning disability,” although achievement was not discrepant from IQ. The coincidence of language impairment with a relative strength in reading belies a unique neuropsychologic profile. Educational programming for these children must address both verbal and nonverbal deficits. (J Pediatr 1999;134:193-8)

Testing: Exploring the WISC‐III as a measure of giftedness∗

This study investigated patterns of WISC‐III IQ subtest scores for gifted children. Subtest scatter of WISC‐III scores occurred with greater frequency in a gifted sample than for subjects reported in the test manual's normative sample. Variability from the subtest mean of the gifted was most evident on Similarities, Comprehension, Coding, and Symbol Search. The extent of subtest scatter and its pattern on the WISC‐III was similar to typical patterns of highs and lows found for gifted children on the WISC‐R with one notable exception. There was a marked lack of strength in Block Design, previously seen as a peak subtest for gifted students when assessed with the WISC‐R.

P300 from amnesic patients with bilateral hippocampal lesions

P3(00) event-related brain potentials (ERPs) were recorded using auditory and visual stimuli from 5 amnesic patients with confirmed (n = 4) or suspected (n = 1) bilateral damage to the hippocampal formation without skull defects. Four normal control subjects were matched to each amnesic patient with respect to age, sex, education, and IQ subtest scores (n = 20 total controls). All 5 amnesic patients exhibited ERPs, and no reliable differences in P3 amplitude or latency could be detected between the patients and the control subjects in either modality. The findings indicate that the hippocampal formation does not contribute significantly to the scalp-recorded P3 from auditory and visual target stimuli, a conclusion also supported by additional recent findings from studies of patients with extensive bilateral medial temporal lobe damage studies. The significance of the P3 component for cognitive processing is discussed.

Comparative Efficacy of K-ABC Subtests VS. WISC-R Subtests in the Differential Classification of Learning Disabilities

Comparison of IQ-subtest scores has gained new popularity with the recent introduction of the Kaufman Assessment Battery for Children (K-ABC). The present study addressed questions pertinent to the utility of K-ABC subtests in differentiating LD children from students classified as EMR, SEM, and referred but Unclassified. In addition, it directly compared the efficacy of K-ABC subtests vs. subtests from the Wechsler Intelligence Scale for Children-Revised (WISC-R) in this task. The sample consisted of 265 children (181 males, 84 females) referred for psychological evaluations; 171 were classified LD. The LD group was further divided into two subgroups: those who showed significant ability-achievement discrepancies (LDdisc; n = 42) and those who did not (LDno; n = 129). Hierarchical discriminant-function analyses showed that subtest scores from both the K-ABC and the WISC-R differentiated the LDdisc group from children in the other categories. However, subsequent classification analyses revealed that neither the K-ABC nor the WISC-R was capable of returning children to their correct placements. Results, therefore, indicate that subtest scores from the K-ABC and the WISC-R were incapable of enhancing the differential classification of LD over rates obtainable on the basis of chance.