Factor Structure of the 10 WISC-V Primary Subtests Across Four Standardization Age Groups

Measurement Invariance of the WISC-V across a Clinical Sample of Children and Adolescents with ADHD and a Matched Control Group

Measurement invariance of the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) 10-primary subtest battery was analyzed across a group of children and adolescents with ADHD (n = 91) and a control group (n = 91) matched by sex, age, migration background, and parental education or type of school. First, confirmatory factor analyses (CFAs) were performed to establish the model fit for the WISC-V second-order five-factor model in each group. A sufficiently good fit of the model was found for the data in both groups. Subsequently, multigroup confirmatory factor analyses (MGCFAs) were conducted to test for measurement invariance across the ADHD and control group. Results of these analyses indicated configural and metric invariance but did not support full scalar invariance. However, after relaxing equality constraints on the Vocabulary (VC), Digit Span (DS), Coding (CD), Symbol Search (SS), and Picture Span (PS) subtest intercepts as well as on the intercepts of the first-order factors Working Memory (WM) and Processing Speed (PS), partial scalar invariance could be obtained. Furthermore, model-based reliability coefficients indicated that the WISC-V provides a more precise measurement of general intelligence (e.g., represented by the Full-Scale IQ, FSIQ) than it does for cognitive subdomains (e.g., represented by the WISC-V indexes). Group comparisons revealed that the ADHD group scored significantly lower than the control group on four primary subtests, thus achieving significantly lower scores on the corresponding primary indexes and the FSIQ. Given that measurement invariance across the ADHD and the control group could not be fully confirmed for the German WISC-V, clinical interpretations based on the WISC-V primary indexes are limited and should only be made with great caution regarding the cognitive profiles of children and adolescents with ADHD.

Investigating the Structure of the French WISC-V (WISC-VFR) for Five Age Groups Using Psychometric Network Modeling

Since the seminal work of Spearman, exploratory and confirmatory factor analysis represents the standard method of examining the dimensionality of psychological instruments. Recently, within the network psychometrics approach, a new procedure was proposed to estimate the dimensionality of psychological instruments: exploratory graph analysis (EGA). This study investigated the structure of the French Wechsler Intelligence Scale for Children-Fifth Edition (WISC-VFR) with five standardization sample age groups (6-7, 8-9, 10-11, 12-13, and 14-16 years) using EGA. The primary research questions include (a) how many WISC-VFR dimensions are identified in each age subgroup? (b) how are subtest scores associated within the dimensions? Because the number and the content of the dimensions identified by EGA could vary with samples, the secondary research questions include (c) is there evidence of reproducibility and generalizability of the dimensions identified by EGA? We used another procedure called bootstrap exploratory graph analysis (bootEGA). EGA and bootEGA suggested only three dimensions, which are consistent with processing speed, verbal comprehension, and the "old" perceptual reasoning factor. Results did not support the distinction between visual-spatial and fluid reasoning dimensions. EGA and bootEGA represent new tools to assess the construct validity of psychological instruments, such as the WISC-VFR.

Factorial Validity of the German KABC-II at Ages 7 to 12 in a Clinical Sample: Four Factors Fit Better than Five

Multidimensional intelligence test batteries such as the KABC-II are widely used in clinical practice. Although validity evidence should be provided for all intended uses of a test, data on the factorial validity of the KABC-II mostly relies on the standardization samples and raises some concerns about the adequacy of the factor structure. Confirmatory factor analyses of the KABC-II core subtests were conducted in a sample of 627 children who had been assessed in German Centers for Social Pediatrics. The standard structure of the KABC-II was superior to unidimensional models but, as in previous research, evidenced cross-loadings and a high correlation between Planning/Gf and Simultaneous/Gv. Pattern Reasoning was more closely related to Simultaneous/Gv than to Planning/Gf. A four-factorial structure combining subtests from Planning/Gf and Simultaneous/Gv to form a common factor emerged as a better representation of the data. Story Completion showed a secondary loading on Knowledge/Gc. On average, most subtest variance was accounted for by the general factor. Models with bonus points for fast responses generally fitted worse than those without. Clinicians should be aware that Planning/Gf and Simultaneous/Gv measure both visual and fluid abilities. Scales of the KABC-II should not be interpreted as dimensions independent of the general factor.

Bootstrap Exploratory Graph Analysis of the WISC-V with a Clinical Sample

One important aspect of construct validity is structural validity. Structural validity refers to the degree to which scores of a psychological test are a reflection of the dimensionality of the construct being measured. A factor analysis, which assumes that unobserved latent variables are responsible for the covariation among observed test scores, has traditionally been employed to provide structural validity evidence. Factor analytic studies have variously suggested either four or five dimensions for the WISC-V and it is unlikely that any new factor analytic study will resolve this dimensional dilemma. Unlike a factor analysis, an exploratory graph analysis (EGA) does not assume a common latent cause of covariances between test scores. Rather, an EGA identifies dimensions by locating strongly connected sets of scores that form coherent sub-networks within the overall network. Accordingly, the present study employed a bootstrap EGA technique to investigate the structure of the 10 WISC-V primary subtests using a large clinical sample (N = 7149) with a mean age of 10.7 years and a standard deviation of 2.8 years. The resulting structure was composed of four sub-networks that paralleled the first-order factor structure reported in many studies where the fluid reasoning and visual-spatial dimensions merged into a single dimension. These results suggest that discrepant construct and scoring structures exist for the WISC-V that potentially raise serious concerns about the test interpretations of psychologists who employ the test structure preferred by the publisher.

The Use of Cognitive Tests in the Assessment of Dyslexia

In this literature review, we address the use of cognitive tests, including intelligence tests, in the assessment and diagnosis of dyslexia, from both historic and present-day perspectives. We discuss the role of cognitive tests in the operationalization of the concepts of specificity and unexpectedness, two constructs considered essential to the characterization of dyslexia since the publication of early case reports in the late nineteenth century. We review the advantages and disadvantages of several approaches to specific learning disabilities' identification that are used in schools. We also discuss contemporary debates around the use of standardized cognitive testing in dyslexia evaluations, in particular, the arguments of those who favor an approach to diagnosis based on prior history and the results of a comprehensive evaluation and those who favor an approach based on an individual's response to intervention. We attempt to explain both perspectives by examining clinical observations and research findings. We then provide an argument for how cognitive tests can contribute to an accurate and informed diagnosis of dyslexia.

Factor Structure and Criterion-Related Validity of the Air Force Officer Qualifying Test Form T for Pilot Applicants

The Air Force Officer Qualifying Test (AFOQT) is the primary selection tool for officer applicants in the U.S. Air Force (USAF) for nearly seven decades. The AFOQT is revised and modified periodically, with rigorous equating and linking effort to ensure comparability and connectivity across forms. The most recent version of AFOQT is Form T that includes 10 cognitive ability and knowledge subtests. Despite the continuing validation effort of the AFOQT across forms, it was mostly directed to the general population of officer applicants, but not to any specific subpopulation. The current investigation reported three studies in an attempt to provide evidence for factor structure and criterion-related validity of AFOQT Form T for pilot applicants via four analytical approaches: meta-analysis, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and structural equation modeling (SEM). The results suggested that AFOQT Form T data are best represented by a bifactor model with a general ability and four specific abilities, and that each latent construct has a distinct predictive utility for pilot performance criteria.

The Validity of WISC-V Profiles of Strengths and Weaknesses

The Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V; Wechsler, 2014 ) provides a general intelligence score, representing g, and five index scores, reflecting underlying broad factors. Within person differences between the overall performance across subtests and index scores, denoted as index difference scores, are often used to examine profiles of strengths and weaknesses. In this study, the validity of such profiles was examined for the Dutch WISC-V. In line with previous studies, broad factors explained little variance in index scores. A simulation study showed that variation in index difference scores also reflected little broad factor variance. The simulation study further revealed that, as a consequence, a significant discrepancy between an index score and overall performance was accompanied in only 40%–74% of the cases by a discrepancy on the underlying broad factor. Overall, these results provide little support for the validity and thereby clinical use of WISC-V profiles.

Intelligenz‍(tests) verstehen und missverstehen

Zusammenfassung. Die vorliegende Standortbestimmung zeigt die hohe wissenschaftliche Qualität der Intelligenzforschung und von Intelligenztests. Es werden aber auch mögliche Missverständnisse und Einseitigkeiten der Ergebnisrezeption und -interpretation thematisiert. Im Einzelnen werden (1) die hohe prognostische und kriterienbezogene Validität bei gleichzeitigen Vorbehalten wie teils niedriger Akzeptanz bzw. Augenscheinvalidität, (2) die Darstellung empirischer Befunde aus der Perspektive ausgewählter Theorien sowie (3) die Bedeutung von Umwelteinflüssen und hohen Erblichkeitskoeffizienten eingehender betrachtet. Für jeden dieser Bereiche wird verdeutlicht, dass vor allem Präzision bei der Rezeption und Darstellung von Forschungsergebnissen notwendig ist, um Einseitigkeiten, Missverständnisse und Instrumentalisierungen zu vermeiden. Der vorliegende Beitrag zeigt, dass einiges, was als Problem der Intelligenzforschung und von Intelligenztests kritisiert wird, letztendlich auf die dargestellten Missverständnisse zurückzuführen ist. Vor diesem Hintergrund wird der Unterschied zwischen der qualitativ hochwertigen Intelligenzforschung und Intelligenztestung einerseits sowie den Missverständnissen und Einseitigkeiten bei der Rezeption andererseits herausgearbeitet. Weiterhin werden berechtigte Kritikpunkte an der Intelligenzforschung und an Intelligenztests sowie Forschungsdesiderata benannt.

A Validated WISC-V Short-Form to Estimate Intellectual Functioning in Very Preterm Children at Early School Age

Very preterm children (gestational age < 32 weeks) frequently show neurodevelopmental difficulties (Inattention/dysexecutiveness) throughout their life-stages. A scarcity of resources, along with this population’s cognitive vulnerability, makes the neuropsychological evaluation of these children both complicated and time-consuming. This study aimed to develop a specific and valid Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V) short-form to estimate intellectual functioning in this population. Eighty-four very preterm children (39 female; mean age = 6.50; SD: 0.06) were assessed with the WISC-V. Short-forms were developed following two independent strategies: a) multiple linear regressions for each index; b) correlational analyses between scores on all administered subtests and Full-Scale IQ. Validity of short-forms was analyzed. A short-form (Vocabulary, Matrix Reasoning, Picture Span, and Symbol Search) that satisfied 2/3 validation criteria was proposed. This validated short-form could facilitate the identification of cognitive difficulties in very preterm children, so that they could benefit from early care and support services, avoiding long assessment procedures.

Revisiting the Factor Structure of the German WISC-V for Clinical Interpretability: An Exploratory and Confirmatory Approach on the 10 Primary Subtests

With the exception of a recently published study and the analyses provided in the test manual, structural validity is mostly uninvestigated for the German version of the Wechsler Intelligence Scale for Children - Fifth Edition (WISC-V). Therefore, the main aim of the present study was to examine the latent structure of the 10 WISC-V primary subtests on a bifurcated extended population-representative German standardization sample (N=1,646) by conducting both exploratory (EFA; n=823) and confirmatory (CFA; n=823) factor analyses on the original data. Since no more than one salient subtest loading could be found on the Fluid Reasoning (FR) factor in EFA, results indicated a four-factor rather than a five-factor model solution when the extraction of more than two suggested factors was forced. Likewise, a bifactor model with four group factors was found to be slightly superior in CFA. Variance estimation from both EFA and CFA revealed that the general factor dominantly accounted for most of the subtest variance and construct reliability estimates further supported interpretability of the Full Scale Intelligence Quotient (FSIQ). In both EFA and CFA, most group factors explained rather small proportions of common subtest variance and produced low construct replicability estimates, suggesting that the WISC-V primary indexes were of lower interpretive value and should be evaluated with caution. Clinical interpretation should thus be primarily based on the FSIQ and include a comprehensive analysis of the cognitive profile derived from the WISC-V primary indexes rather than analyses of each single primary index.

Exploratory Factor Analyses of the French WISC-V (WISC-VFR) for Five Age Groups: Analyses Based on the Standardization Sample

This study investigated the factor structure of the French Wechsler Intelligence Scale for Children–Fifth Edition with five standardization sample age groups (6-7, 8-9, 10-11, 12-13, 14-16 years) using hierarchical exploratory factor analysis followed by Schmid–Leiman procedure. The primary research questions included (a) how many French Wechsler Intelligence Scale for Children–Fifth Edition factors should be extracted and retained in each age subgroup, (b) how are subtests associated with the latent factors, (c) was there evidence for the publisher’s claim of five first-order factors and separate Visual Spatial and Fluid Reasoning factors, (d) what proportion of variance was due to general intelligence versus the first-order group ability factors following a Schmid–Leiman procedure, and (e) do results support the age differentiation hypothesis? Results suggested that four factors might be sufficient for all five age groups and results did not support the distinction between Visual Spatial and Fluid Reasoning factors. While the general factor accounted for the largest portions of variance, the four first-order factors accounted for small unique portions of variance. Results did not support the age differentiation hypothesis because the number of factors remained the same across age groups, and there was no change in the percentage of variance accounted for by the general factor across age groups.

An independent examination of the equivalence of the standard and digital administration formats of the Wechsler Intelligence Scale for Children-5th Edition

A new administration format for the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V; Wechsler, 2014) was introduced in 2016 on Q-interactive, Pearson's digital platform for test administration and scoring. The current study examined the measurement unit equivalence of the WISC-V standard and digital administration formats using counter-balanced administration of the 10 primary subtests to measure intellectual ability. The results indicated that correlations (r) between standard scores on subtests and composites administered in each format were generally moderate, with mean rs of 0.64 for subtests and 0.71 for composites after correction for attenuation, with the lowest rs for processing speed. Split-plot ANOVAs were conducted to examine within-subjects main effects for administration format and order and their interaction. The results of these analyses revealed significant main effects for format for the Full Scale IQ and Processing Speed composite scores, with small to medium effect sizes (ds > 0.40). These format effects largely stemmed from the non-equivalence of the Coding subtest, which is used to derive both composites. For Coding, the main effect for format was statistically significant, with a large effect size (d = 0.69). Statistically significant administration order by format interaction effects were also observed for a number of composites and subtests, with medium to large effect sizes (ƞ_ps² > 0.20). In each case, higher mean scores were observed when the WISC-V was administered first in digital format. Implications of these results for research and practice are discussed.

Long-term stability of Wechsler Intelligence Scale for Children-fifth edition scores in a clinical sample

This study investigated the stability of Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V) scores for 225 children and adolescents from an outpatient neuropsychological clinic across, on average, a 2.6 year test-retest interval. WISC-V mean scores were relatively constant but subtest stability score coefficients were all below 0.80 (M = 0.66) and only the Verbal Comprehension Index (VCI), Visual Spatial Index (VSI), and omnibus Full Scale IQ (FSIQ) stability coefficients exceeded 0.80. Neither intraindividual subtest difference scores nor intraindividual composite difference scores were stable across time (M = 0.26 and 0.36, respectively). Rare and unusual subtest and composite score differences as well as subtest and index scatter at initial testing were unlikely to be repeated at retest (kappa = 0.03 to 0.49). It was concluded that VCI, VSI, and FSIQ scores might be sufficiently stable to support normative comparisons but that none of the intraindividual (i.e. idiographic, ipsative, or person-relative) measures were stable enough for confident clinical decision making.

Validity of the WISC-V in Youth with Autism Spectrum Disorder: Factor Structure and Measurement Invariance

Objective: Assessment of intellectual abilities in individuals with autism spectrum disorder (ASD) is a core component of a comprehensive diagnostic evaluation. However, relatively limited information is available regarding the validity of one of the most commonly-used measures of intelligence, the Wechsler Intelligence Scale for Children - 5th Edition (WISC-V) in ASD.Method: We investigated the factor structure and measurement invariance of the WISC-V in a sample of 349 children aged 6-16 diagnosed with ASD using single- and multi-group confirmatory factor analysis. The comparison group was the WISC-V standardization sample.Results: A four-index bifactor solution best fit the ASD group data. Measurement invariance analyses indicated support for configural and metric, but not scalar, invariance of the published 5-index structure, suggesting systematic differences in performance among some subscales in ASD. The 7-subtest FSIQ scale had partial scalar invariance after relaxing equality constraints on the Coding and Digit Span subtest intercepts, suggesting sources other than theorized IQ ability contribute to lower scores on these subtests within ASD. The Cognitive Proficiency Index (CPI) failed to demonstrate appropriate fit in baseline models. The General Ability Index (GAI) had full configural, metric, and scalar invariance.Conclusions: Statistical bias on the WISC-V within ASD in processing speed and working memory subtests creates significant limitations for the use of FSIQ and especially CPI index scores in ASD populations. The GAI showed strong measurement properties and should be considered as the preferred indicator of overall intellectual functioning when assessing children with ASD using the WISC-V.

Sex Differences in Intelligence in Children Aged 2:6–7:7: Analysis of the Factor Structure and Measurement Invariance of the German Wechsler Primary and Preschool Scale of Intelligence–Fourth Edition

The present study investigated gender differences in cognitive abilities for children aged 2–7 years on the German Wechsler Primary and Preschool Scale of Intelligence–Fourth Edition (WPPSI-IV). WPPSI-IV data of 1,042 children (517 girls and 525 boys) were selected from the extended dataset of the German WPPSI-IV standardization sample. First of all, confirmatory factor analyses (CFAs) were used to verify the factor structure of the WPPSI-IV, which was proposed by the test developers. Then, multiple-group confirmatory factor models were implemented to explore measurement invariance across gender. Finally, mean differences in the subtests, index scores, as well as full scale IQ (FSIQ) were analyzed. The second-order three-factor model for age group 2:6–3:11 as well as the second-order five-factor model for age group 4:0–7:7 could be verified. For age group 2:6–3:11, full scalar invariance could be accepted, whereas partial scalar invariance could be established by freeing five nonequivalent subtest intercepts for age group 4:0–7:7. These findings support interpretable comparisons of the WPPSI-IV scores between girls and boys. For age group 4:0–7:7, partial invariance should be taken into account in these comparisons. Furthermore, girls aged 4:0–7:7 showed an advantage in processing speed (PS). Mean scores in any of the other cognitive abilities did not differ between girls and boys in both age groups. These results indicated measurement invariance across gender on the WPPSI-IV, so that the tests measure cognitive abilities in the same way for girls and boys. The current findings showed that gender differences in PS may emerge in early childhood, which might lead to gender differences in later educational skills.

Measurement Invariance of the Wechsler Intelligence Scale for Children, Fifth Edition 10-Subtest Primary Battery: Can Index Scores be Compared across Age, Sex, and Diagnostic Groups?

Measurement invariance of the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) 10 subtest primary battery was evaluated across sex, age (6–8, 9–11, 12–14, and 15–16 year-olds), and three diagnostic (attention-deficit/hyperactivity disorder, anxiety, and encephalopathy) groups within a large clinical sample ( N = 5359) referred to a children’s specialty hospital. Competing models were tested using confirmatory factor analysis (CFA), and a five-factor oblique model corresponding to the publisher’s hypothesized first-order measurement model (e.g., verbal comprehension, fluid reasoning, visual-spatial, working memory, and processing speed) was found to have the best model fit. Multigroup CFA was subsequently used to evaluate progressively more restrictive constraints on the measurement model. Results indicated that full metric invariance was attained across the three groups studied. Full scalar invariance was attained for sex and diagnostic groups. Partial scalar invariance was attained for age-group. The results of this study provide support for the first-order scoring structure of the five WISC-V factors in the 10 subtest primary battery with this large clinical sample.

Examination of five- and four-subtest short form IQ estimations for the Wechsler Intelligence Scale for Children-Fifth edition (WISC-V) in a mixed clinical sample

Evaluating general cognitive ability (i.e., intelligence) is common in neuropsychological practice, and identifying abbreviated assessments of intelligence is often advantageous. Despite the Wechsler Intelligence Scale for Children, Fifth Edition's (WISC-V) widespread contemporary use, limited research has identified clinically useful short form (SF) full scale IQ (FSIQ) estimations in clinical samples. This study sought to address this gap in the literature. Two hundred sixty-eight pediatric participants (M age = 9.79; 69% male; 88% Caucasian/White) who underwent psychological/neuropsychological evaluation were included. Mean scores for WISC-V scores fell in the low average-to-average ranges, consistent with the clinical nature of this sample (e.g., M FSIQ = 85.3). Ten unique SF combinations with five (pentad) and four (tetrad) subtests, each intentionally selected to represent a breadth of domains subsumed by WISC-V FSIQ, were described by summing subtest age-corrected scaled scores. Regression-based and prorated FSIQ estimates were calculated, and mean differences suggested some prorated estimates should be arithmetically adjusted. Both regression-based and prorated/adjusted methods provided FSIQ estimates that were accurate within five Standard Score points of true FSIQ for approximately 81-92% (pentad) and 65-76% (tetrads) of participants. Prorated/adjusted estimates appeared to provide somewhat better accuracy than regression-based estimates. Relationships between SFs and true FSIQ did not appear to be moderated by participant age, gender, nor how many WISC-V subtests were administered to participants within this archival sample (i.e., 7 vs. 10). Implications of these findings, including benefits, detriments, and other considerations of each SF combination, in addition to limitations of this study, are discussed in detail.

Use of translated and adapted versions of the WISC-V: Caveat emptor

The Wechsler Intelligence Scale for Children (WISC) is the most widely used intelligence test in the world. Now in its fifth edition, the WISC-V has been translated and adapted for use in nearly a dozen countries. Despite its popularity, numerous concerns have been raised about some of the procedures used to develop and validate translated and adapted versions of the test around the world. The purpose of this article is to survey the most salient of those methodological and statistical limitations. In particular, empirical data are presented that call into question the equating procedures used to validate the WISC-V Spanish, suggesting cautious use of that instrument. It is believed that the issues raised in the present article will be instructive for school psychologists engaged in the clinical assessment of intelligence with the WISC-V Spanish and with other translated and adapted versions around the world.

Monte Carlo Modeling of Contemporary Intelligence Test (IQ) Factor Structure: Implications for IQ Assessment, Interpretation, and Theory

Researchers continue to debate the constructs measured by commercial ability tests. Factor analytic investigations of these measures have been used to develop and refine widely adopted psychometric theories of intelligence particularly the Cattell-Horn-Carroll (CHC) model. Even so, this linkage may be problematic as many of these investigations examine a particular instrument in isolation and CHC model specification across tests and research teams has not been consistent. To address these concerns, the present study used Monte Carlo resampling to investigate the latent structure of four of the most widely used intelligence tests for children and adolescents. The results located the approximate existence of the publisher posited CHC theoretical group factors in the Differential Abilities Scales-Second edition and the Kaufman Assessment Battery for Children-Second edition but not in the Wechsler Intelligence Scale for Children-Fifth edition or the Woodcock-Johnson IV Tests of Cognitive Abilities. Instead, the results supported alternative conceptualizations from independent factor analytic research. Additionally, whereas a bifactor model produced superior fit indices in two instruments (Wechsler Intelligence Scale for Children-Fifth edition and Woodcock-Johnson IV Tests of Cognitive Abilities), a higher order structure was found to be superior in the Kaufman Assessment Battery for Children-Second edition and the Differential Abilities Scales-Second edition. Regardless of the model employed, the general factor captured a significant portion of each instrument's variance. Implications for IQ test assessment, interpretation, and theory are discussed.

Measurement Invariance Across Gender on the Second-Order Five-Factor Model of the German Wechsler Intelligence Scale for Children-Fifth Edition

The present study investigated measurement invariance across gender on the German Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V). The higher order model that was preferred by the test publishers was tested on a population-representative German sample of 1,411 children and adolescents aged between 6 and 16 years. Confirmatory factor analyses were conducted to test for measurement invariance. As soon as partial scalar invariance could be established by freeing nonequivalent subtest intercepts, results demonstrated that 11 out of 15 subtest scores have the same meaning for male and female children. These findings support interpretable comparisons of the WISC-V test scores between males and females but only in due consideration of partial scalar invariance and with respect to the underlying factor structure. Despite this, however, results did not support the overall structural validity of the higher order model. Thus, replacing the former Perceptual Reasoning factor by Fluid Reasoning and Visual Spatial may be considered inappropriate due to the redundancy of the FRI as a separate factor. Results also indicated that the WISC-V provides stronger measurement of general intelligence (Full Scale IQ) than measurements of cognitive subdomains (WISC-V indexes). Interpretative emphasis should thus be placed on the Full Scale IQ rather than the WISC-V indexes.

Exploratory Factor Analyses of the Intelligence and Development Scales-2: Implications for Theory and Practice

The factor structure of the intelligence and scholastic skills domains of the Intelligence and Development Scales-2 was examined using exploratory factor analyses with the standardization and validation sample (N = 2,030, aged 5 to 20 years). Results partly supported the seven proposed intelligence group factors. However, the theoretical factors Visual Processing and Abstract Reasoning as well as Verbal Reasoning and Long-Term Memory collapsed, resulting in a five-factor structure for intelligence. Adding the three scholastic skills subtests resulted in an additional factor Reading/Writing and in Logical-Mathematical Reasoning showing a loading on abstract Visual Reasoning and the highest general factor loading. A data-driven separation of intelligence and scholastic skills is not evident. Omega reliability estimates based on Schmid-Leiman transformations revealed a strong general factor that accounted for most of the true score variance both overall and at the group factor level. The possible usefulness of factor scores is discussed.

Construct Validity of the WISC-V in Clinical Cases: Exploratory and Confirmatory Factor Analyses of the 10 Primary Subtests

Independent exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) research with the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V) standardization sample has failed to provide support for the five group factors proposed by the publisher, but there have been no independent examinations of the WISC-V structure among clinical samples. The present study examined the latent structure of the 10 WISC-V primary subtests with a large (N = 2,512), bifurcated clinical sample (EFA, n = 1,256; CFA, n = 1,256). EFA did not support five factors as there were no salient subtest factor pattern coefficients on the fifth extracted factor. EFA indicated a four-factor model resembling the WISC-IV with a dominant general factor. A bifactor model with four group factors was supported by CFA as suggested by EFA. Variance estimates from both EFA and CFA found that the general intelligence factor dominated subtest variance and omega-hierarchical coefficients supported interpretation of the general intelligence factor. In both EFA and CFA, group factors explained small portions of common variance and produced low omega-hierarchical subscale coefficients, indicating that the group factors were of poor interpretive value.

Investigating the Theoretical Structure of the Differential Ability Scales—Second Edition Through Hierarchical Exploratory Factor Analysis

When the Differential Ability Scales–Second Edition (DAS-II) was developed, the instrument’s content, structure, and theoretical orientation were amended. Despite these changes, the Technical Handbook did not report results from exploratory factor analytic investigations, and confirmatory factor analyses were implemented using selected subtests across the normative age groups from the total battery. To address these omissions, the present study investigated the theoretical structure of the DAS-II using principal axis factoring followed by the Schmid–Leiman procedure with participants from the 5- to 8-year-old age range to determine the degree to which the DAS-II theoretical structure proposed in the Technical Handbook could be replicated. Unlike other age ranges investigated where at most 14 subtests were administered, the entire DAS-II battery was normed on participants aged 5 to 8 years, making it well suited to test the full instrument’s alignment with theory. Results suggested a six-factor solution that was essentially consistent with the Cattell–Horn–Carroll (CHC)-based theoretical structure suggested by the test publisher and simple structure was attained. The only exception involved two subtests (Picture Similarities and Early Number Concepts) that did not saliently load on a group factor. Implications for clinical practice are discussed.