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Individually administered intelligence measures are commonly used in diagnostic work, but there is a continuing need for research investigating possible test bias among these measures. One current intelligence measure, the Differential Ability Scales, Second Edition (DAS-II), is a test with growing popularity. The issue of test bias, however, has not been thoroughly investigated with the DAS-II. The current study investigated whether the DAS-II demonstrates systematic construct bias when used with children from three racial and ethnic groups—African American, Asian, and Hispanic—when compared to non-Hispanic Caucasian children. Multi-group confirmatory factor analyses with data from the DAS-II standardization sample were used to assess whether the constructs and measurement of constructs were invariant across groups. Results indicate cross-group internal structure validity in the DAS-II, and thus a lack of construct bias. Minor differences were found, but these differences do not affect the calculation of composite scores on the DAS-II and thus would not result in unfair scoring for the groups involved. Results of this study support the appropriateness of the DAS-II for clinical use with these racial and ethnic groups.

There is a paucity of literature examining the relationship between executive and social functioning in children with autism spectrum disorder (ASD). Twenty-three school-aged children with ASD participated. Executive functioning was measured using the Developmental Neuropsychological Assessment, Second Edition and Differential Ability Scales, Second Edition, and the teacher-rated Behavior Rating of Inventory of Executive Function. Independent assessors observed children’s social functioning on the playground while children with ASD and their peers completed a survey to measure peer friendships and rejections. Overall, poorer executive functioning was associated with increased playground isolation and less engagement with peers. This suggests that metacognitive skills such as initiation, working memory, and planning and organization are associated with children’s social functioning.

One major risk of paediatric sleep apnoea-hypopnoea syndrome (SAHS) is the development of cognitive impairments among affected children. Electroencephalography (EEG) is ordinarily used as part of polysomnography, the standard diagnostic test for SAHS. However, how SAHS changes overnight EEG, and its relationships with cognitive performance, remains unclear. In this study, we first analyzed the spectral content of EEG recordings from 294 children to explore possible differences caused by SAHS. Then, a correlation network analysis was conducted to evaluate relationships among different EEG spectral bands and the results from the Differential Ability Scales (DAS) battery of cognitive tests. Our analyses identified up to six new SAHS spectral bands of interest in the EEG. They also showed higher absolute correlations among the different spectral bands as SAHS severity increased. Higher SAHS severity degree also indicated higher absolute correlations with DAS tests. Our results suggest that the spectral content of the overnight EEG is useful to characterize both paediatric SAHS and the cognitive performance of the affected children.

BACKGROUND: Studies have revealed an association between positional plagiocephaly and/or brachycephaly (PPB) and development, although little is known about long-term outcomes. We examined cognition and academic achievement in children with and without PPB, testing the hypothesis that children who had PPB as infants would score lower than controls. METHODS: We enrolled 187 school-aged children with a history of PPB and 149 controls. Exposures were the presence or absence and severity of infancy PPB (mild, moderate to severe). Cognitive and academic outcomes were assessed by using the Differential Ability Scales, Second Edition and Wechsler Individual Achievement Test, Third Edition, respectively. RESULTS: Children with PPB scored lower than controls on most scales of the Differential Ability Scales, Second Edition (standardized effect sizes [ESs] = −0.38 to −0.20) and the Wechsler Individual Achievement Test, Third Edition (ESs = −0.22 to −0.17). Analyses by PPB severity revealed meaningful differences among children with moderate to severe PPB (ESs = −0.47 to −0.23 for 8 of 9 outcomes), but few differences in children with mild PPB (ESs = −0.28 to 0.14). CONCLUSIONS: School-aged children with moderate to severe PPB scored lower than controls on cognitive and academic measures; associations were negligible among children with mild PPB. The findings do not necessarily imply that these associations are causal; rather, PPB may serve as a marker of developmental risk. Our findings suggest a role for assessing PPB severity in clinical practice: providing developmental assessment and intervention for infants with more severe deformation and reassurance and anticipatory guidance for patients with mild deformation.

Aim To assess the predictive validity at 4 years of the Movement Assessment Battery for Children - Second Edition (MABC-2) for motor impairment at 8 years in children born preterm. We also aimed to determine if sex, cognition, medical, or social risks were associated with motor impairment at 8 years or with a change in MABC-2 score between 4 years and 8 years. Method Ninety-six children born at less than 30 weeks’ gestation were assessed with the MABC-2 at 4 years and 8 years of age. Motor impairment was defined as less than or equal to the 5th centile. The Differential Ability Scales - Second Edition (DAS-II) was used to measure General Conceptual Ability (GCA) at 4 years, with a score

Aim To evaluate the relationship between corticotropin-releasing hormone (CRH) expression in the placenta and the risk of school-related dysfunctions at the age of 10 years among children born extremely preterm (EP). Methods Corticotropin-releasing hormone expression was measured in the placenta of 761 EP children, who had the following assessments at the age of 10 years: Differential Ability Scales, Oral and Written Language Scales, the Wechsler Individual Achievement Test-III, NEPSY-II and the Child Symptom Inventory-4. We evaluated whether lowest and highest quartiles of CRH mRNA were associated with undesirable scores on these assessments. With 272 evaluations, we would expect 14 to be significant at p Results Only 16 associations were statistically significant. On the other hand, seven of these were social limitations among girls whose placenta CRH mRNA was in the top quartile. Adjusting for delivery indication or restricting the sample to one delivery indication group resulted in few differences. Conclusion Overall, placenta CRH mRNA concentrations in the top or bottom quartiles were not associated with increased risks of dysfunctions 10 years later. Girls whose placenta CRH expression was in the top quartile, however, were at increased risk of seven indicators/correlates of social limitations.

OBJECTIVES:To compare neurocognitive, language, executive function, academic achievement, neurologic and behavioral outcomes, and quality of life at age 10 years in children born extremely preterm who developed bronchopulmonary dysplasia (BPD) to children who did not develop BPD.METHODS:The Extremely Low Gestational Age Newborns study population included 863 children born extremely preterm whose BPD status before discharge was known had an IQ (Differential Ability Scales II [DAS II]) assessment at 10 years. We evaluated the association of BPD with any cognitive (DAS II), executive function (NEuroPSYchological Assessment II), academic achievement (Wechsler Individual Achievement Test-III and Oral and Written Language Scales [OWLS]) as well as social dysfunctions (Social Responsiveness Scale). We used logistic regression models, adjusting for potential confounding factors, to assess the strength of association between the severity of BPD and each outcomes.RESULTS:Three hundred and seventy-two (43%) children were oxygen-dependent at 36 weeks postconception age, whereas an additional 78 (9%) were also oxygen- and ventilator-dependent. IQ scores 2 or more SDs below the expected mean (ie, z scores ≤−2) occurred twice as commonly among children who had BPD as among those who did not. Children with severe BPD consistently had the lowest scores on DAS II, OWLS, Wechsler Individual Achievement Test-III, NEuroPSYchological Assessment II, and Social Responsiveness Scale assessments.CONCLUSIONS:Among 10-year-old children born extremely preterm, those who had BPD were at increased risk of cognitive, language, and executive dysfunctions; academic achievement limitations; social skill deficits; and low scores on assessments of health-related quality of life.

This randomized field trial comparing Strategies for Teaching based on Autism Research and Structured Teaching enrolled educators in 33 kindergarten-through-second-grade autism support classrooms and 119 students, aged 5–8 years in the School District of Philadelphia. Students were assessed at the beginning and end of the academic year using the Differential Ability Scales. Program fidelity was measured through video coding and use of a checklist. Outcomes were assessed using linear regression with random effects for classroom and student. Average fidelity was 57% in Strategies for Teaching based on Autism Research classrooms and 48% in Structured Teaching classrooms. There was a 9.2-point (standard deviation = 9.6) increase in Differential Ability Scales score over the 8-month study period, but no main effect of program. There was a significant interaction between fidelity and group. In classrooms with either low or high program fidelity, students in Strategies for Teaching based on Autism Research experienced a greater gain in Differential Ability Scales score than students in Structured Teaching (11.2 vs 5.5 points and 11.3 vs 8.9 points, respectively). In classrooms with moderate fidelity, students in Structured Teaching experienced a greater gain than students in Strategies for Teaching based on Autism Research (10.1 vs 4.4 points). The results suggest significant variability in implementation of evidence-based practices, even with supports, and also suggest the need to address challenging issues related to implementation measurement in community settings.

Recently emerging evidence suggests that the dominant structural model of mental abilities-the Cattell-Horn-Carroll (CHC) model-may not adequately account for observed scores for mental abilities batteries, leading scholars to call into question the model's validity. Establishing the robustness of these findings is important since CHC is the foundation for several contemporary mental abilities test batteries, such as the Woodcock-Johnson III (WJ-III). Using confirmatory factor analysis, we investigated CHC's robustness across 4 archival samples of mental abilities test battery data, including the WJ-III, the Kaufman Adolescent & Adult Intelligence Test (KAIT), the Kaufman Assessment Battery for Children (KABC), and the Differential Ability Scales (DAS). We computed omega hierarchical (ωH) and omega subscale (ωS) coefficients for g and the broad factors, which estimated the relationship of composite scores to g and the broad factors, respectively. Across all 4 samples, we found strong evidence for a general ability, g. We additionally found evidence for 3 to 9 residualized, orthogonal broad abilities existing independently of g, many of which also explained reliable variance in test battery scores that cannot be accounted for by g alone. The reliabilities of these broad factors, however, were less than desirable (i.e.

Considerable animal research and available human studies suggest that psychological distress experienced by mothers during gestation is associated with later neurodevelopmental deficits in offspring; however, little research has examined potential protective factors that might mitigate this risk. The current study examined the impact of maternal prenatal psychological distress during pregnancy on cognitive outcomes in preschoolers (ages 2.5-5 years) and positive parenting as a potential protective factor. Mother-child dyads (N = 162, mean child age = 44 months, 49 % female) were recruited from a longitudinal cohort of women who had previously participated in a study of maternal mood disorders during pregnancy. Maternal prenatal distress was assessed with multiple measures collected throughout pregnancy. During a follow-up visit, mothers were interviewed about their psychological symptoms since the birth of the child, parenting behaviors were recorded during a parent-child interaction, and children's cognitive abilities were measured using the Differential Ability Scales, 2nd Edition. Maternal prenatal distress significantly predicted lower general cognitive abilities; however, this relationship was strongest for children whose mothers exhibited low levels of positive engagement and not significant when mothers exhibited high levels of positive engagement. Results suggest that positive parental engagement can protect against the detrimental effects of maternal prenatal distress on preschoolers' cognitive abilities.

Sleep-disordered breathing (SDB) in children is associated with cognitive challenges. However, potential associations between SDB severity and neurocognitive function, as well as the presence of an SDB cutoff, have not been fully explored.To determine whether SDB-associated adverse changes in neurocognitive functioning are severity dependent.A total of 1,010 snoring and nonsnoring children ages 5-7 years were prospectively recruited from public schools and underwent polysomnography and neurocognitive assessments of intellectual, attention, memory, language, and executive function development. The children were subdivided into four severity groups on the basis of apnea-hypopnea index (AHI), followed by comparisons of cognitive function, with a particular focus on standardized subtests of intellectual, language, attention, memory, and executive function.Differential Ability Scales Verbal (P 0.001) and Nonverbal (P = 0.002) performance, as well as global conceptual ability (IQ) (P 0.001) scores, differed significantly across the groups, with individuals with higher AHI showing worse performance. Additionally, specific NEPSY (a Developmental Neuropsychological Assessment) subscores focused on attention and executive skills differed across the groups, indicating differences in levels of engagement and problem solving. Children with higher AHI (5 per hour of total sleep time) were significantly more impaired than all three lower AHI groups, indicating a dose-response impact of SDB.This large community-based sample of children highlights the significant deleterious impact of SDB, particularly in children with moderate to severe obstructive sleep apnea, and also that even snoring alone affects neurocognitive function. By affecting developing capabilities, as illustrated by cognitive measures in a severity-graded manner, SDB could adversely impact children's capacity to attain academic and adaptive goals, ultimately hampering their ability to reach independence. Our findings support the need for increased awareness of SDB, with particular emphasis on children with more severe obstructive sleep apnea.

Research Findings: The present study used a longitudinal design to identify how sleep habits and learning-related behaviors impact the development of cognitive skills in preschoolers (ages 3–5). Sixty- seven children with parental report and cognitive skill assessment data were included. Scores on the Differential Ability Scales (C. Elliott, 1990) were obtained at ages 3, 4, and 5. A Sleep Questionnaire (D. Gozal, 1998) with 12 items from the Child Behavior Checklist (T. M. Achenbach & L. A. Rescorla, 2000) related to children's attention and activity levels was administered at age 3. Growth curve changes in cognitive scores were estimated using hierarchical linear modeling. Parental reports of nighttime sleep duration predicted level of cognitive skills at 3 years. The effect of sleep duration on cognitive scores was constant across age. Practice or Policy: Sleep and learning-related behaviors distinguish the cognitive skills children bring to preschool programs and impact gains made in skills while in p...

Concerns about the ability-achievement discrepancy method for specific learning disability (SLD) determination led to alternative research-based methods, such as failure to respond to intervention. Neither of these regulatory methods address the statutory SLD definition, which explicitly includes a deficit in basic psychological processes. Examining neuropsychological processing differences among typical children and children with math SLD, commonality analyses revealed that Differential Ability Scales – Second Edition (DAS-II) predictors accounted for more achievement variance in typical children (46% to 58%) than in children with math SLD (33% to 50%), with substantial loss of predictive validity when General Conceptual Ability was used instead of subcomponent scores. Results suggest that differences in typical predictor-outcome relationships may provide a foundation for developing specific cognitive and academic interventions for children with math SLD. © 2008 Wiley Periodicals, Inc.

Some researchers have argued that discrepant broad index scores invalidate IQs, but others have questioned the fundamental logic of that argument. To resolve this debate, the present study used a nationally representative sample of children (N 1,200) who were matched individually for IQ. Children with significantly uneven broad index score profiles and those with even broad index score profiles had equivalent reading and math skills. Discrepant broad index scores found in only 15%, 10%, 5%, and 1% of the population, respectively, also failed to differentially predict academic achievement. In addition, significantly higher Verbal broad index scores were not differentially predictive of reading achievement, nor were significantly higher Nonverbal/Spatial broad index scores differentially predictive of math achievement. It was concluded that the global ability score is the most parsimonious predictor of academic achievement, despite the presence of significant and rare variability among broad index scores.

Although there has been a substantial growth in the number of published studies examining tests of cognitive abilities and using contemporary theories of cognitive abilities, to date none have done so with preschool cognitive tests. In this study the relation between cognitive ability measures for young children and Cattell-Horn-Carroll (CHC) theory is examined. Tests and subtests from the Differential Ability Scales: Upper Preschool Level and the Woodcock-Johnson Tests of Cognitive Ability-Revised with a sample of 158 children between 4 and 5 years of age were used in a series of joint factor analyses. Although a series of models were explored, the model representative of the CHC theory of cognitive abilities was best supported by the data. This provides evidence for a greater differentiation of young children's cognitive abilities than are typically interpreted. Results are discussed with regard to understanding the link between contemporary theories of intelligence and young children's cognitive abilit...

Processing speed subtests are components of widely used intellectual assessment instruments. Many researchers interpret these measures as assessing a unitary construct, but there is a question concerning the constructs assessed by these measures and, ultimately, their interpretative utility. Coding and Symbol Search from the Wechsler Intelligence Scale for Children-Third Edition (Wechsler, 1991), Visual Matching and Cross Out from the Woodcock Johnson Tests of Cognitive Ability-Revised (Woodcock & Johnson, 1989), and Speed of Information Processing from the Differential Ability Scales (Elliott, 1990) were administered to 102 volunteer participants. Using regression analyses, performance on each of these tests was predicted by motor speed and/or number facility factors. Individual differences in motor speed were found to be related to each of the five processing speed measures, whereas number facility was related to three of the measures.

The purpose of this study was to examine the utility of the Differential Ability Scales (DAS) in distinguishing preschoolers with specific language impairment (SLI) and specific subtypes of language delays. Three hundred forty-eight language-impaired preschoolers' response patterns across DAS General Conceptual Ability (GCA), Ability cluster, and subtest scores were compared to response profiles of 57 preschoolers without language impairment as well as the standardized mean. Participants' specific type of language impairment (Articulation, Expressive, Receptive, Pragmatic, Expressive-Receptive, Expressive-Articulation, Receptive-Articulation, and Articulation-Pragmatic) was then compared to their response patterns. Results indicated that, in general, SLI preschoolers had significantly lower GCA, Verbal Ability, Nonverbal Ability, and subtest scores on the DAS compared to preschoolers without language impairment. However, different response patterns across the GCA, Ability clusters, and subtests emerged depending on the SLI subtype. SLI children with Articulation-only impairments tended to score higher on Ability Cluster and subtest scores, whereas children with Receptive and Expressive-Receptive impairment scored lowest. Discriminant analysis revealed that subtype profiles could predict SLI subtype in 26% to 38% of the cases. Finally, factor analysis indicated a new factor structure for both younger and older preschool batteries, suggesting that practitioners working with the SLI-referred population should carefully consider the utility of the original DAS factors.

This study investigated the structure of the Differential Ability Scales (DAS; Elliott, 1990a) using confirmatory factor analysis with 130 normal school-aged children. Maximum likelihood estimation, using the six Core subtests, found an extremely good fit with the data and supported the DAS model proposed by Elliott (1990a). In addition, the six Core subtests were found to be strong measures of g, supporting their contribution to the General Conceptual Ability. Replication of Keith's (1990) final model, which included the six Core subtests and three Diagnostic subtests, was also conducted. This model was based on the same theoretical framework against which Keith (1990) tested his models. This theoretical framework was derived from a logical analysis of the nature of the subtests in light of prior research. The present study found a reasonably good fit for the data when the model included both the Core and Diagnostic subtests.

Past literature has largely ignored the population frequency of multivariate factor and subtest score discrepancies. Another limitation has been that statistical models imperfectly model the clinical assessment process, whereby significant discrepancies between both factors and subtests are included in predictions about an individual’s academic achievement. The present study examined these issues using a nationally representative sample (N = 1,185) completing the Differential Ability Scales. Results indicate that approximately 80% of children in a nonreferred sample show at least one statistically significant ability discrepancy. In addition, the global estimate of cognitive ability was the most parsimonious predictor of academic achievement, whereas information about ability discrepancies did not significantly improve prediction. Findings suggest that when predicting academic achievement, there is little value in interpreting cognitive scores beyond the global ability estimate.

This paper describes the procedures that can be used by school professionals to translate the directions of a test from one language (English) to another (Spanish). The procedures were then applied to the translation of four nonverbal Differential Ability Scale subtests into Spanish. The translation of these directions is provided in an appendix. The performance of a referred population of 97 Spanish speaking children, who were given the translated directions, mirrors that of children in the DAS standardization sample. Evidence from internal validity coefficients, concurrent validity coefficients, and construct validity suggests that the DAS nonverbal subtests can be translated and yield information comparable to non-translation. The translation provided makes possible a more standard administration of this test to Spanish-speaking children.

IMPORTANCE Breastfeeding is known to have beneficial effects, but concern exists that breastfeeding during maternal antiepileptic drug (AED) therapymay be harmful.We previously noted no adverse effects of breastfeeding associated with AED use on IQ at age 3 years, but IQ at age 6 years is more predictive of school performance and adult abilities. OBJECTIVES To examine the effects of AED exposure via breastfeeding on cognitive functions at age 6 years. DESIGN, SETTING, AND PARTICIPANTS Prospective observational multicenter study of long-term neurodevelopmental effects of AED use. Pregnant women with epilepsy receiving monotherapy (ie, carbamazepine, lamotrigine, phenytoin, or valproate) were enrolled from October 14, 1999, through April 14, 2004, in the United States and the United Kingdom. At age 6 years, 181 children were assessed for whom we had both breastfeeding and IQ data. All mothers in this analysis continued taking the drug after delivery. MAIN OUTCOMES AND MEASURES Differential Ability Scales IQwas the primary outcome. Secondary measures included measures of verbal, nonverbal, memory, and executive functions. For our primary analysis, we used a linear regression model with IQ at age 6 years as the dependent variable, comparing children who breastfed with those who did not. Similar secondary analyses were performed for the other cognitive measures. RESULTS In total, 42.9%of children were breastfed a mean of 7.2 months. Breastfeeding rates and duration did not differ across drug groups. The IQ at age 6 years was related to drug group (P

Previous research has found associations but not established mechanisms of developmental linkage between language ability and inattentive–hyperactive (I-H) behavior problems. The present study examined whether self-regulation mediates the effect of language ability on later I-H behavior problems among young children (N = 120) assessed at 30, 36, and 42 months of age. Cross-lagged panel models tested the direction of effect between language ability and self-regulation and longitudinal effects of language ability on later I-H problems mediated by self-regulation. Language ability was measured by children's scores on the receptive and expressive language subtests of the Differential Ability Scales. Self-regulation was measured by three behavioral tasks requiring inhibitory control. I-H problems were reported by parents and secondary caregivers. Language ability predicted later self-regulation as measured by all three tasks. There was no association, however, between self-regulation and later language ability, suggesting that the direction of effect was stronger from language ability to later self-regulation. Moreover, the effect of language ability on later I-H behavior problems was mediated by children's self-regulation in one of the tasks (for secondary caregivers' but not parents' ratings). Findings suggest that language deficits may explain later I-H behavior problems via their prediction of poorer self-regulatory skills.

OBJECTIVE To test the hypothesis that prenatal exposure to serotonin reuptake inhibitors (SRIs) is associated with language and behavioral outcomes in preschool-aged children, while accounting for confounds such as concomitant exposures and maternal mental illness. METHOD An observational, prospective, longitudinal study of mental illness in pregnancy was conducted at a university-based women's mental health clinic (April 2010-November 2012). A sample of 178 mother-child dyads participated in a laboratory visit at preschool age (2.5-5.5 years). The majority of women (87%) received psychotropic medication during pregnancy. Psychiatric status (based on DSM-IV), other medication use, and substance use were serially assessed and tested as confounds. Primary outcome measures included standardized measures of expressive language and cognitive function and mother and alternate caregiver ratings of child behavior problems, including the Pervasive Developmental Disorders (PDD) subscale of the Child Behavior Checklist. RESULTS Linear regression analyses revealed that, after controlling for relevant covariates, expressive language scores from the Test of Early Language Development, 3rd edition, were negatively associated with prenatal SRI exposure (β = -0.15, t = -2.41), while the PDD behavioral problems subscales completed by alternate caregivers and mothers were positively associated with prenatal SRI exposure (β = 0.17, t = 2.01; β = 0.16, t = 2.00, respectively). Cognitive function, measured using the Differential Ability Scales, 2nd edition, was not associated with any medication exposures. CONCLUSIONS The current data suggest a small but significant association between prenatal SRI exposure and preschool outcomes, including expressive language and behavior problems. These data corroborate data from recent, population-based studies, although overall, published findings are mixed. Replication and identification of moderating risk factors are needed to understand potential clinical implications.

This study examined the cluster profiles obtained using the Differential Ability Scale (DAS, Elliott, 1990a) for preschool children diagnosed with cognitive delay and for those without cognitive delay. Cluster analyses resulted in distinctive profiles for each group. Profiles for preschoolers diagnosed with cognitive delay were compared with DAS profile patterns previously reported for school-aged children diagnosed with learning disabilities (McIntosh & Gridley, 1993). Cluster comparisons indicated profiles of cognitively delayed preschoolers were not the same as those found in school-age children with learning disabilities. Implications for prediction of school-age learning disabilities from preschool DAS cognitive cluster profiles are discussed. © 2002 John Wiley & Sons, Inc.

Intellectual assessment of minority children continues to occupy a position of importance in the practice of school psychology. A review of the extant literature suggests a continuing controversy regarding the adequacy of current intelligence tests to measure the cognitive ability of U.S. minority children. The present study examined the relationship between the DAS, an individually administered cognitive and achievement test developed for use with children and adolescents, and the WISC-III, the most commonly used intelligence test for children. Both the DAS and the WISC-III were administered to a sample of 24 English-speaking Hispanic children between the ages of 9 and 11. Global and factor scores for both tests were compared, with special attention paid to verbal/performance score discrepancies. A relationship between the WISC-III and the DAS was indicated, providing evidence for the convergent validity of the DAS and the WISC-III in assessing English-speaking Hispanic children residing in the United States. Results of the study are further discussed in terms of the use of the DAS in the evaluation of Hispanic students.

The relationship between the Early Screening Profiles (ESP; Harrison, 1990) and the Differential Ability Scales (DAS; Elliott, 1990a) was studied. The participants were 94 (57 males, 37 females) at-risk preschoolers ranging in age from 3 years 6 months to 5 years 11 months (M= 4 years 7 months; SD= 6.3 months). The sample included 72 Caucasians, 21 African Americans, and one Hispanic. This study found that the DAS GCA (General Conceptual Ability) mean score was significantly lower than the ESP Total Screening mean score. However, a strong relationship (r= .78) was found between the ESP Total Screening and DAS GCA scores, indicating that the ESP is a good predictor of cognitive ability among at-risk preschoolers. © 2000 John Wiley & Sons, Inc.

The Differential Ability Scales (DAS) and the Woodcock-Johnson Tests of Cognitive Ability-Revised (WJ-R COG standard battery) were administered to 81 children referred for special education services evaluation. Both the General Conceptual Ability (GCA) and the Nonverbal Reasoning scores of the DAS were significantly lower than the WJ-R COG Broad Cognitive Ability-Standard score (BCA-STD). The DAS Verbal and Spatial Composite scores were not significantly different from the BCA-STD. Low to moderate correlations were found between related constructs on the two tests.

This study evaluated the criterion-related validity for the Speed of Processing (SP) factor of the Differential Ability Scales (DAS; Elliott, 1990). The SP factor is comprised of one subtest score (Speed of Information Processing) based on results from factor analyses. Participants were an epidemiological sample (N= 1,400) stratified, within age levels, in proportion to census data on demography (e.g., race, gender, parents' educational levels). From this cohort, groups with unusual SP strengths and SP weaknesses were identified using General Cognitive Ability (GCA) scores from the DAS as contrasts (i.e., SP>GCA and GCA>SP differences at a population prevalence < 5%). The SP>GCA group (n= 60) and the GCASP group (n = 60) were matched to respective controls (where each control n = 60) on the demographic variables listed above and GCAs. Each group and its control were compared across three norm-referenced measures of achievement and six teacher-rated indices of behavioral adjustment. Comparisons failed to show significant differences on any criterion variable. Results are discussed in the context of how well epidemiological samples evaluate the validity of ability profiles and the need for future research to use more representative measures of processing speed (i.e., those with two or more subtests contributing to the factor).

The Differential Ability Scales (DAS) is a relatively new and well-received measure of intelligence for children and youth ages 21/2 through 17. Although there is evidence to support the construct validity of the DAS, there is little evidence concerning construct bias in the DAS. The purpose of this research was to test for construct bias in the DAS for children from the three major ethnic groups, and across the entire age range of the DAS. We also sought to determine the nature of the constructs measured across these three groups. Both purposes were accomplished through hierarchical, multisample confirmatory factor analysis of DAS standardization data. The research also illustrates the use of this methodology to perform a comprehensive test of construct bias. Results suggest that the DAS measures the same constructs for all three ethnic groups across the four age levels studied; the DAS, therefore, shows no construct bias across groups. Furthermore, the hierarchical factor structure of the test is quite consistent with the DAS's actual structure, thus supporting the construct validity of the DAS. The DAS's Nonverbal reasoning cluster may be a good measure of fluid intelligence.

Horn's distinction between fluid intelligence (Gf) and visualization (Gv) was investigated with two Nonverbal Reasoning subtests from the Differential Ability Scales and three Simultaneous Processing subtests from the Kaufman Assessment Battery for Children. The sample comprised a predominantly Euro-American group of 57 normal boys and girls between the ages of 6 and 12 years. Principal factor analysis yielded clear-cut Gf and Gv dimensions. The Gf factor was composed both of Differential Ability Scales and Kaufman–ABC subtests, suggesting that the construct of simultaneous processing is not merely a measure of Gv, as some researchers have hypothesized, but also measures Horn's Gf fluid intelligence to a considerable extent.

This research evaluated the criterion-related validity of unusual subtest profiles from the Differential Ability Scales (Elliott, 1990). Three methods were used to identify unusual profiles: multiv...

The Differential Ability Scales (DAS) was administered to young children (ages 3 to 6) to determine the appropriateness of the instrument with children with linguistic differences. Specifically, the Special Nonverbal Composite (SNC) of the DAS was investigated for children with linguistic differences and children who speak English as their first language. The ability of the SNC to differentiate children with linguistic differences as opposed to more global developmental delays was also of interest. The children who participated in the study were grouped as: (a) no identified concern, English as primary language (control); (b) identified as having Specific Language Impairment (SLI); (c) identified as Deaf/Hearing Impaired (Deaf/HI); (d) identified as Developmentally Delayed (DD); or (e) no identified developmental concern, English as a Second Language/Limited English Proficiency (ESL/LEP). Children in the SLI, Deaf/HI, and DD groups had been identified previously by their school district, local Speech and Hearing Clinic, or other agency. Children in the ESL/LEP group were from a variety of cultural backgrounds and spoke minimal English. Results indicate that SNC scores obtained for children in the ESL/LEP group were comparable to those obtained by the control group. Children in the SLI and Deaf/HI groups obtained scores lower than those of the control and ESL/LEP groups; however, their scores were significantly higher than those obtained by the children in the DD group. Implications for the use of the SNC in the assessment of young children with linguistic differences are discussed.

The linear loadings of intelligence test composite scores on a general factor (g) have been investigated recently in factor analytic studies. Spearman's law of diminishing returns (SLODR), however, implies that the g loadings of test scores likely decrease in magnitude as g increases, or they are nonlinear. The purpose of this study was to (a) investigate whether the g loadings of composite scores from the Differential Ability Scales (2nd ed.) (DAS-II, C. D. Elliott, 2007a, Differential Ability Scales (2nd ed.). San Antonio, TX: Pearson) were nonlinear and (b) if they were nonlinear, to compare them with linear g loadings to demonstrate how SLODR alters the interpretation of these loadings. Linear and nonlinear confirmatory factor analysis (CFA) models were used to model Nonverbal Reasoning, Verbal Ability, Visual Spatial Ability, Working Memory, and Processing Speed composite scores in four age groups (5-6, 7-8, 9-13, and 14-17) from the DAS-II norming sample. The nonlinear CFA models provided better fit to the data than did the linear models. In support of SLODR, estimates obtained from the nonlinear CFAs indicated that g loadings decreased as g level increased. The nonlinear portion for the nonverbal reasoning loading, however, was not statistically significant across the age groups. Knowledge of general ability level informs composite score interpretation because g is less likely to produce differences, or is measured less, in those scores at higher g levels. One implication is that it may be more important to examine the pattern of specific abilities at higher general ability levels.

As part of a mandated three-year reevaluation, the Differential Ability Scales (DAS) was administered to 53 children identified as having a learning disability approximately 3 years after each had been administered the Wechsler Intelligence Scale for Children—Third Edition (WISC-III). The DAS's General Conceptual Ability score (GCA), and Verbal and Spatial Cluster scores were nonsignificantly different from the WISC-III's Full Scale, Verbal, and Performance scores. The Nonverbal Reasoning score of the DAS (a measure of Fluid intelligence not assessed by the WISC-III) was significantly different from both the Verbal and Performance scores. High correlations were found between the similar constructs on the two tests. Approximately 96% of the students obtaining a certain classification from the WISC-III obtained a comparable classification from the DAS. © 1996 John Wiley & Sons, Inc.