Factorial invariance of the Wechsler Intelligence Scale for Children, Fifth Edition, across the UK, US and Australia & New Zealand

OBJECTIVES

This study examined the factorial invariance of the factor structure of the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) across the UK, US and Australia & New Zealand (A&NZ). The factorial equivalence of cognitive assessments should be demonstrated before assuming cross-culture generalizability and interpretations of score comparisons.

METHODS

Data were obtained from the UK, US and A&NZ normative standardizations of the WISC-V. The samples consisted of 415 UK, 2200 US and 528 A&NZ children, aged 6-16. Confirmatory factor analysis was applied separately in each sample to establish the baseline model. Next, tests of factorial invariance were undertaken using the recommended hierarchical approach, firstly across the UK and A&NZ samples and then across the UK and US samples.

RESULTS

The five-factor first-order scoring model was found to be excellent fit across all three samples independently. Strict factorial invariance of the WISC-V was demonstrated firstly across the UK and A&NZ and secondly the UK and US nationally representative standardization samples. Comparison of latent means found small but significant differences in female children across the UK and A&NZ samples.

CONCLUSIONS

Consistent with previous research, these results demonstrate the generality of the WISC-V factor structure across the UK, US and A&NZ. Furthermore, as the WISC-V factor structure aligns with the Cattell-Horn-Carroll (CHC) model of cognitive abilities, the results add further support to the cross-cultural generalizability of the CHC model. Small but significant differences in latent factor scores found across samples support the development and use of local normative data.

Cross-National Generalizability of WISC-V and CHC Broad Ability Constructs across France, Spain, and the US

The Cattell-Horn-Carroll (CHC) model is based on psychometric cognitive ability research and is the most empirically supported model of cognitive ability constructs. This study is one in a series of cross-national comparisons investigating the equivalence and generalizability of psychological constructs which align with the CHC model. Previous research exploring the cross-cultural generalizability of cognitive ability measures concluded that the factor analytic models of cognitive abilities generalize across cultures and are compatible with well-established CHC constructs. The equivalence of the psychological constructs, as measured by the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V), has been established across English-speaking samples. However, few studies have explored the equivalence of psychological constructs across non-English speaking, nationally representative samples. This study explored the equivalence of the WISC-V five-factor model across standardization samples from France, Spain, and the US. The five-factor scoring model demonstrated excellent fit across the three samples independently. Factorial invariance was investigated and the results demonstrated strict factorial invariance across France, Spain, and the US. The results provide further support for the generalizability of CHC constructs across Western cultural populations that speak different languages and support the continued use and development of the CHC model as a common nomenclature and blueprint for cognitive ability researchers and test developers. Suggestions for future research on the CHC model of intelligence are discussed.

Cognitive predictors of language abilities in primary school children: A cascaded developmental view

This study investigated the longitudinal relationship between children's domain-general cognitive constraints underlying phonological and sentence processing development in a big sample of typically developing children. 104 children were tested on non-linguistic processing speed, phonological skills (phonological short term memory, phonological knowledge, phonological working memory), and sentence processing abilities (sentence repetition and receptive grammar) in 1^st grade (aged 6 to 6.5) and one year later. A cross-lagged structural equation model showed that non-linguistic processing speed was a concurrent predictor of phonological skills, and that phonology had a powerful effect on the child's sentence processing abilities concurrently and longitudinally, providing clear evidence for the role of domain-general processes in the developmental pathway of language. These findings support a cascaded cognitive view of language development and pose important challenges for evaluation and intervention strategies in childhood.

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.

What assessments are currently used to investigate and diagnose cerebral visual impairment (CVI) in children? A systematic review

PURPOSE

Cerebral visual impairment (CVI) is the leading cause of childhood visual impairment in the developed world. Despite this, there are no agreed clinical guidelines for the investigation and diagnosis of the condition. Before development of such guidelines can commence, it is important to recognise which approaches are currently employed. This systematic review evaluated the literature to identify which methods of assessment are currently used to investigate and diagnose childhood CVI.

METHODS

Medline, Embase, CINAHL, Scopus and the Cochrane Library databases were systematically searched in January 2020 using defined search terms. Articles were included if they: (i) were research papers, conference abstracts or research protocols published in peer-reviewed scientific journals, or relevant textbooks; (ii) included a clinical investigation of CVI in children; (iii) provided an explanation or criteria to diagnose CVI and (iv) were specifically investigating cerebral/cortical visual impairment. Methods used to a) assess and b) diagnose CVI were extracted from included articles. 'Assessment scores' were assigned for each method employed by researchers to investigate and diagnose CVI to quantify and compare approaches between articles. A quality grading was also applied to each article.

RESULTS

Of 6454 identified articles, 45 met the inclusion criteria. From these, 10 categories of assessment utilised within included articles were identified: (1) Medical history, (2) Vision assessment/ophthalmologic examination, (3) Neuroimaging, (4) Visual behaviour and direct observation, (5) Structured history-taking, (6) Visual perception tests, (7) Ocular movement and posture assessment, (8) Intelligence/IQ assessment, (9) Clinical electrophysiology and (10) Neurodevelopmental tests. In terms of diagnostic criteria, the most commonly reported approach was one of exclusion, i.e., CVI was diagnosed when visual dysfunction could not be attributed to abnormalities detected in the anterior visual pathway.

CONCLUSION

There is a lack of common practice in the approaches used by clinicians to investigate and diagnose CVI in children. At present, a 'diagnosis of exclusion' remains the most common means to diagnose CVI. Development of clinical guidelines for assessment and diagnosis are necessary to ensure consistency in the diagnosis of CVI and the timely implementation of support to alleviate the impact of CVI on the child's daily living.

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.

Anxiety-Related Attention Bias in Four- to Eight-Year-Olds: An Eye-Tracking Study

(1) Background: There is evidence of an attention bias–anxiety relationship in children, but lack of appropriate methods has limited the number of studies with children younger than eight years old. This study used eye tracking as a measure of overt attention in young children. The aim of this study was to assess anxiety-related attention bias in children aged four to eight years. Age was considered a moderator, and the influence of effortful control was investigated. (2) Method: A community sample of 104 children was shown pairs of happy–neutral and angry–neutral faces. Growth curve analyses were used to examine patterns of gaze over time. (3) Results: Analyses revealed moderation by age and anxiety, with distinct patterns of anxiety-related biases seen in different age groups in the angry–neutral face trials. Effortful control did not account for age-related effects. (4) Conclusions: The results support a moderation model of the development of anxiety in children.

Age and Gender Invariance in the Taiwan Wechsler Intelligence Scale for Children, Fifth Edition: Higher Order Five-Factor Model

This study investigated the factorial invariance of the Taiwan Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V) across age and gender. A higher order five-factor model was tested on a nationally representative sample of 1,034 children aged 6–16 years. The results demonstrated full factorial invariance for Taiwan children of different ages and gender. The WISC-V subtests demonstrated the same underlying theoretical latent constructs, strength of relations among factors and subtests, validity of each first-order factor, and communalities, regardless of age and gender, which supported the same interpretive approach of the WISC-V. These results accord with findings in the United States, indicating a full factorial invariance of the WISC-V five-factor structure across ages and gender.

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.

Look out captain, I hear an ambiguous alien! A study of interpretation bias and anxiety in young children

There is convincing evidence that anxious children and adolescents are biased to interpret ambiguity in a negative way (Stuijfzand, Creswell, Field, Pearcey, & Dodd, 2017). However, little research examines interpretation bias in children under eight years. This is due to existing measures of interpretation bias being inappropriate for young children. Consequently, we aimed to develop a new interpretation bias task for young children using tones. Children learnt to associate high tones with a 'happy alien' and low tones with an 'angry alien'. They were then asked to classify tones from the middle of the frequency range (ambiguous tones) as 'happy' or 'angry'. Corrugator muscle activity was recorded alongside behavioural responses. A community sample of 110 children aged 4-8 years, split into high and low anxious groups, completed the task. High anxious children were more likely to interpret the ambiguous tones as negative but this effect was small and only apparent after controlling for developmental factors. Corrugator activity aligned with behavioural responses for trained but not ambiguous tones. This is the first study to assess interpretation bias in young children using behavioural and physiological measures. Results indicate the task is developmentally appropriate and has potential utility for future research.

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.

The Impacts of a Reading-to-Dog Programme on Attending and Reading of Nine Children with Autism Spectrum Disorders

Simple Summary

The purpose of this research was to compare reading motivation and attitude, as well as reading and cognitive skills, of school-age children diagnosed with Autism Spectrum Disorders (ASD) who attended a 10 session reading programme with and without the presence of a dog. Children who read to a dog had 100% attendance at sessions over the course of the programme versus 75% (range 25–100%) of children attending reading sessions without a dog. In addition, after the programme, they were significantly more motivated and willing to read at home, as perceived by their parents. However, there were no significant differences in scores on reading and cognitive tests either within each group or between groups. Based on these results, we can conclude that reading to a dog can have positive effects on an ASD child’s motivation and attitude toward reading. More research is needed to better understand if it can also have positive effects on children with ASD’s overall reading and cognitive abilities.

Abstract

Poor knowledge is available on the effectiveness of reading to dogs in educational settings, particularly in children with Autism Spectrum Disorders (ASD). In this study, we test the hypothesis that reading to a dog improves propensity towards books and motivation to read after the end of the programme, as well as reading and cognitive skills in children with ASD. The study is a prospective, randomized controlled trial, consisting of testing and re-testing after a 10 sessions reading programme with and without the presence of a dog. Nine Children with ASD (6–11 years old) were randomly assigned to a control (CG, reading without a dog, n. 4) or experimental group (EG, reading to a dog, n. 5). Children’s attendance at reading sessions was recorded at each session. Parents’ perceptions were evaluated at the end of the programme to detect changes in children’s attitudes and motivation toward reading. Psychologist-administered validated reading (Cornoldi’s MT2 reading test; test of reading comprehension, TORC; metaphonological competence test, MCF) and cognitive tests (Wechsler intelligence scale for children Wisc IV, Vineland) to all children, at baseline and at the end of the reading programme. Compared with CG children, children in the EG group participated more frequently in the reading sessions, and they were reported to be more motivated readers at home after the programme. However, there were no differences on reading and cognitive tests’ scores either within each group of children or between groups. Further studies are warranted in order to understand whether and how incorporating dogs into a reading programme is beneficial to Children with ASD at the socio-emotional and cognitive level.

Neural anticipatory mechanisms predict faster reaction times and higher fluid intelligence

Higher cognitive ability is reliably linked to better performance on chronometric tasks (i.e., faster reaction times, RT), yet the neural basis of these effects remains unclear. Anticipatory processes represent compelling yet understudied potential mechanisms of these effects, which may facilitate performance through reducing the uncertainty surrounding the temporal onset of stimuli (temporal uncertainty) and/or facilitating motor readiness despite uncertainty about impending target locations (target uncertainty). Specifically, the contingent negative variation (CNV) represents a compelling candidate mechanism of anticipatory motor planning, while the alpha oscillation is thought to be sensitive to temporal contingencies in perceptual systems. The current study undertook a secondary analysis of a large data set (n = 91) containing choice RT, cognitive ability, and EEG measurements to help clarify these issues. Single-trial EEG analysis in conjunction with mixed-effects modeling revealed that higher fluid intelligence corresponded to faster RT on average. When considered together, temporal and target uncertainty moderated the RT-ability relationship, with higher ability being associated with greater resilience to both types of uncertainty. Target uncertainty attenuated the amplitude of the CNV for all participants, but higher ability individuals were more resilient to this effect. Similarly, only higher ability individuals showed increased prestimulus alpha power (at left-lateralized sites) during longer, more easily anticipated interstimulus intervals. Collectively, these findings emphasize top-down anticipatory processes as likely contributors to chronometry-ability correlations.

Fluid Reasoning Mediates the Association of Birth Weight With ADHD Symptoms in Youth From Multiplex Families With ADHD

OBJECTIVE

We tested mediation of birth weight and ADHD symptoms by multiple biologically plausible neurocognitive functions and evaluated familiality of observed indirect effects.

METHOD

647 youth from 284 multiplex families with ADHD completed the Arithmetic, Digit Span, Vocabulary, and Block Design subtests of the Wechsler Intelligence Scale for Children (WISC). Multiple mediation tested WISC subtests as mediators of birth weight and multi-informant ADHD symptoms. Familiality of indirect effects was estimated via moderated mediation comparing conditional indirect effects across siblings concordant and discordant for ADHD.

RESULTS

Controlling for IQ and demographic factors, Arithmetic uniquely mediated birth weight and ADHD symptoms. Conditional indirect effects through Arithmetic did not differ across ADHD concordant and discordant siblings.

CONCLUSION

These cross-sectional findings support previous prospective longitudinal research implicating Arithmetic (i.e., fluid reasoning) as a preliminary causal mediator of birth weight and ADHD symptoms, and suggest that this pathway is independent of genetic influences on ADHD.

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.

Short Forms of Wechsler Scales Assessing the Intellectually Gifted Children Using Simulation Data

Intellectual giftedness is usually defined in terms of having a very high Intellectual Quotient (IQ). The intellectual capacity is assessed by a standardized test such as the Wechsler Intelligence Scale for Children (WISC). However, the identification of intellectually gifted children (IGC) often remains time-consuming. A short-form WISC can be used as a screening instrument. The practitioners and researchers in this field can then make a more in-depth evaluation of the IGC's cognitive and socioemotional characteristics if needed. The aim of our study is thus to determine the best short tests, in terms of their psychometric qualities, for the identification of IGC. The current study is composed of three-step analyses. Firstly, we created nine IQs short forms (IQ_SF) with 2-subtests, and nine IQ_SF with 4-subtests from the WISC-IV (Wechsler, 2005). Secondly, we estimated psychometric parameters (i.e., reliability and validity) from empirical and simulated dataset with WISC-IV. The difference in the estimation of psychometric qualities of each IQ_SF from the simulated data is very close to those derived from empirical data. We thus selected the three best IQ_SF based on these psychometrics parameters estimated from simulated datasets. For each selected short form of the WISC-IV, we estimated the screening quality in our sample of IGC. Thirdly, we created IQ_SF with 2- and 4-subtests from the WISC-V (Wechsler, 2016) with simulated dataset. We then highlighted the three best short forms of WISC-V based on the estimated psychometric parameters. The results are interpreted in terms of validity, reliability and screening quality of IGC. In spite of the important changes in the WISC-V, our findings show that the 2-subtest form, Similitaries + Matrix Reasoning, and 4-subtest form, Similitaries + Vocabulary + Matrix Reasoning + Block Design, are the most efficient to identify the IGC at the two recent versions of Wechsler scales. Finally, we discuss the advantages and drawbacks of a brief assessment of intellectual aptitudes for the identification of the IGC.

Structural Validity of the WISC-IV for Students With ADHD

OBJECTIVE

To evaluate the structural validity of the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV).

METHOD

Confirmatory factor analyses were applied to a sample of 233 students diagnosed with ADHD by school multidisciplinary evaluation teams to evaluate the relative fit of the following competing models: (a) one factor, (b) two oblique verbal and nonverbal factors, (c) three oblique verbal, perceptual, and combined working memory/processing speed factors, (d) four oblique verbal, perceptual, working memory, and processing speed factors, (e) a higher-order model with four first-order factors, and (f) a bifactor model with four domain-specific factors.

RESULTS

A higher-order four-factor model fit the data best, which was composed of a general intelligence factor and four domain-specific factors that matched the four factors specified in the WISC-IV technical and interpretive manual. Moreover, the general intelligence factor explained more than two times the total variance contributed by all four domain-specific factors combined.

CONCLUSIONS

Results substantiate previous research on the WISC-IV, indicating that the general intelligence factor contributes the most reliable information. Consequently, it is recommended that interpretation of the WISC-IV remain at the Full-Scale IQ score level.

Pathways from Birth Weight to ADHD Symptoms through Fluid Reasoning in Youth with or without Intellectual Disability

Although individual differences in fluid reasoning reliably mediate predictions of attention-deficit/hyperactivity disorder (ADHD) symptoms from birth weight in youth with typical cognitive development (TD), it is unknown if this indirect effect operates similarly in the development of ADHD symptoms secondary to intellectual disability (ID). Thus, we evaluated mediation by fluid reasoning in a longitudinal sample of 163 youth (45% female) with (n = 52) or without (n = 111) ID who were followed prospectively from age 5 to age 13. At age 9, youth completed the Arithmetic subtest of the Wechsler Intelligence Scale for Children, a measure of fluid reasoning. At ages 9 and 13, mothers and teachers separately rated youth ADHD symptoms and mothers completed a diagnostic interview. Mediation was tested via path analysis with bootstrapped confidence intervals, and moderated mediation estimated whether indirect effects differed between ID and TD youth or based on youth IQ. Controlling for demographic factors and age 9 ADHD symptoms, age 9 Arithmetic mediated birth weight and multi-method/informant age 13 ADHD symptoms, such that birth weight positively predicted Arithmetic, which negatively predicted ADHD symptoms. Neither ID status nor IQ moderated the observed indirect effect through Arithmetic, suggesting that it was similar for ID and TD youth as well as across the range of youth IQs. These findings support previous evidence that fluid reasoning, as measured by Arithmetic, may causally mediate birth weight and ADHD symptoms, and suggest that this pathway operates similarly with respect to the development of ADHD symptoms in youth with ID.

COMT and DAT1 polymorphisms moderate the indirect effect of parenting behavior on youth ADHD symptoms through neurocognitive functioning

Although gene × environment interactions contribute to youth attention-deficit/hyperactivity disorder (ADHD) symptoms, the pathways mediating these influences are unknown. We tested genetic moderation of indirect effects from parenting behavior to youth ADHD symptoms through multiple neurocognitive factors. Two hundred and twenty-nine youth with and without ADHD were assessed at baseline (Wave 1; ages 5-10) and at a 2-year follow-up (Wave 2; ages 7-13). At Wave 1, youth completed a neurocognitive battery including measures of response inhibition, visuospatial working memory, and fluid reasoning, and a standardized parent-child interaction task yielding observational measures of positive and negative parenting. At Wave 2, youth psychopathology was rated by parents and teachers using multiple methods (i.e., structured interview, rating scale). We employed moderated multiple mediation and compared conditional indirect effects across youth genotypes at two biologically plausible genetic loci. Controlling for parent ADHD symptoms as well as youth demographic factors and co-occurring externalizing symptoms, these genetic factors moderated the indirect effect from Wave 1 parenting to multi-method/informant Wave 2 ADHD symptoms through Wave 1 neurocognitive functioning. This preliminary study is the first to identify genetic moderation of mediated effects underlying ADHD symptoms and suggests that specific gene × parenting interactions may underlie neurocognitive functioning deficits and subsequent ADHD.

Orthogonal Higher Order Structure of the WISC-IV Spanish Using Hierarchical Exploratory Factor Analytic Procedures

As recommended by Carroll, the present study examined the factor structure of the Wechsler Intelligence Scale for Children–Fourth Edition Spanish (WISC-IV Spanish) normative sample using higher order exploratory factor analytic techniques not included in the WISC-IV Spanish Technical Manual. Results indicated that the WISC-IV Spanish subtests were properly aligned with theoretically proposed factors; however, application of the Schmid and Leiman procedure found that the g factor accounted for large portions of total and common variance, whereas the four first-order factors accounted for small portions of total and common variance. Implications for clinical interpretation of the measurement instrument are discussed.

Neurocognitive Functioning Mediates the Prospective Association of Birth Weight With Youth ADHD Symptoms

Although birth weight is a potential causal risk factor for attention-deficit/hyperactivity disorder (ADHD) symptoms, both the specificity of this association and its mediating pathways are largely unknown. We carefully assessed youth with and without ADHD (i.e., Wave 1), and followed them prospectively for 2 years (i.e., Wave 2). We (a) tested the association of birth weight with Wave 2 ADHD symptoms, and (b) evaluated biologically plausible neurocognitive functions from Wave 1 as temporally ordered mediators of birth weight and Wave 2 ADHD symptoms in a multiple mediation framework. At Wave 1, 222 ethnically diverse youth (30% female; ages 5-10) completed the Digit Span, Vocabulary, Symbol Search, and Arithmetic subtests of the Wechsler Intelligence Scale for Children-IV. At both Wave 1 and Wave 2 (ages 7-13), multiple informants (i.e., parents, teachers) rated youth ADHD symptoms and co-occurring psychopathology using multiple methods (i.e., structured interview, rating scale). Controlling for demographic factors, gestational age, and co-occurring externalizing and internalizing psychopathology, birth weight inversely predicted Wave 2 ADHD symptoms across multiple methods and informants. Additionally, controlling for Wave 1 ADHD symptoms and relevant covariates, Wave 1 Arithmetic uniquely mediated the association of birth weight with multi-method/informant Wave 2 ADHD symptoms. These findings suggest that birth weight is a relatively specific risk factor for youth ADHD symptoms and they implicate individual differences in fluid reasoning as a preliminary causal mediator of this association. We discuss implications for future research evaluating causal mechanisms underlying risk factors for ADHD.

The Cattell–Horn–Carroll Model of Cognition for Clinical Assessment

The Cattell–Horn–Carroll (CHC) model is a comprehensive model of the major dimensions of individual differences that underlie performance on cognitive tests. Studies evaluating the generality of the CHC model across test batteries, age, gender, and culture were reviewed and found to be overwhelmingly supportive. However, less research is available to evaluate the CHC model for clinical assessment. The CHC model was shown to provide good to excellent fit in nine high-quality data sets involving popular neuropsychological tests, across a range of clinically relevant populations. Executive function tests were found to be well represented by the CHC constructs, and a discrete executive function factor was found not to be necessary. The CHC model could not be simplified without significant loss of fit. The CHC model was supported as a paradigm for cognitive assessment, across both healthy and clinical populations and across both nonclinical and neuropsychological tests. The results have important implications for theoretical modeling of cognitive abilities, providing further evidence for the value of the CHC model as a basis for a common taxonomy across test batteries and across areas of assessment.

Structural Validity of the WISC-IV for Students With Learning Disabilities

The structural validity of the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) was evaluated using confirmatory factor analysis for a clinical sample of 1,537 students diagnosed with specific learning disabilities (SLD) by school psychologists in two large southwestern school districts. Results indicated that a bifactor model consisting of four first-order domain specific factors and a general intelligence breadth factor fit the data best. Consequently, the structural validity of the WISC-IV for students with SLD was supported by the results of the present study. The general intelligence factor contributed the most information, accounting for 48% of the common variance. Given this structure, it was recommended that score interpretation should emphasize the Full-Scale IQ score because of the marginal contributions of the first-order domain-specific factors and their low precision of measurement independent of the general factor.

Investigation of the Factor Structure of the Comprehensive Test of Nonverbal Intelligence–Second Edition (CTONI-2) Using Exploratory Factor Analysis

The present study examined the structure of the Comprehensive Test of Nonverbal Intelligence–Second Edition (CTONI-2) normative sample using exploratory factor analysis, multiple factor extraction criteria, and higher-order exploratory factor analytic techniques that were not reported in the in the CTONI-2 Examiner’s Manual. Results indicated that retention of the hypothesized CTONI-2 measurement model resulted in several theoretically inconsistent factor loadings, low factor loadings, and the retention of impermissible factors (e.g., factors with no salient loadings). Hierarchical exploratory analyses with the Schmid and Leiman procedure found that the second-order g factor accounted for large portions of total and common variance, in contrast to the two first-order factors that accounted for small portions of dimensional variance. Results suggest that the CTONI-2 provides a strong measure of general intelligence and clinical interpretation should be limited to that level of the measurement instrument.

What Does the Shipley-2 Measure for Children and Adolescents? Integrated and Conjoint Confirmatory Factor Analysis With the WISC-IV

We used integrated and conjoint confirmatory factor analysis of Shipley-2 and Wechsler Intelligence Scale for Children–Fourth Edition (WISC-IV) data to investigate constructs measured in the Shipley-2 for children and adolescents. We also estimated Shipley-2 composite reliability at the subtest level rather than the item level. The three Shipley-2 subtests for the most part measured what was described in the manual, although Block Patterns measured visual spatial ability in addition to fluid ability and Abstraction was best considered a measure of psychometric g. The g factors derived from the WISC-IV and Shipley-2 were similar but not identical. Internal reliability estimates for Shipley-2 composites that were based on correlations between the subtests were substantially lower than those based on the items. Last, based on WISC-IV derived g factors, 37% to 53% of the variance in Shipley-2 composites was explained by g. Some of the reliable variance in the Shipley-2 composites was due to something specific that the subtests had in common not explained by psychometric g.

Broad and Narrow CHC Abilities Measured and Not Measured by the Wechsler Scales

In this commentary, we reviewed two clinical validation studies on the Wechsler Scales conducted by Weiss and colleagues. These researchers used a rigorous within-battery model-fitting approach that demonstrated the factorial invariance of the Wechsler Intelligence Scale for Children–Fourth Edition (WISC-IV) and Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV) across populations. Beyond the important finding of invariance across populations, however, these studies did not provide much additional clarification about exactly what is and what is not measured by the WISC-IV and WAIS-IV vis-à-vis an overarching empirically validated theory of the structure of cognitive abilities. To that end, we argued that a better understanding of the cognitive constructs (both broad and narrow) measured by the Wechsler scales or invariance across selection of variables is necessary and will require theory-driven joint or cross-battery confirmatory factor analysis. Recommendations for conducting this type of research were offered within the context of the Cattell-Horn-Carroll theory of cognitive abilities.

What If We Took Our Models Seriously? Estimating Latent Scores in Individuals

Researchers often argue that the structural models of the constructs they study are relevant to clinicians. Unfortunately, few clinicians are able to translate the mathematically precise relationships between latent constructs and observed scores into information that can be usefully applied to individuals. Typically this means that when a new structural model supplants a rival model, clinicians have only vague (and often incorrect) notions about how score interpretations should change. Fortunately, it is possible to estimate latent scores from observed scores in a rigorous manner. More important, paying attention to the confidence intervals around those estimates can assist clinicians’ intuitions about what can (and cannot) be known with precision about a person’s abilities. These methods are illustrated with structural models of the WISC-IV (Wechsler Intelligence Scale for Children—Fourth Edition). A free user-friendly spreadsheet that automates these procedures is available from the author.

WAIS-IV and WISC-IV Structural Validity

Weiss, Keith, Zhu, and Chen (2013a) and Weiss, Keith, Zhu, and Chen (2013b), this issue, report examinations of the factor structure of the Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV) and Wechsler Intelligence Scale for Children–Fourth Edition (WISC-IV), respectively; comparing Wechsler Hierarchical Model (W-HM) and Cattell–Horn–Carroll Hierarchical Model (CHC-HM), subtest cross-loadings, and factorial invariance between clinical and normative groups from the respective standardizations. Both studies suffer from a number of theoretical, methodological, and practical problems that significantly limit conclusions and recommendations for practitioner interpretations of these instruments. Additional analyses and research are required to better inform practitioners for WAIS-IV and WISC-IV use.

Intelligent Testing With Wechsler’s Fourth Editions

The two featured articles and eight commentaries on the WISC-IV (Wechsler, 2003) and WAIS-IV (Wechsler, 2008) in this special issue of Journal of Psychoeducational Assessment are of exceptional quality. As a collective, this special issue greatly advances the field of cognitive assessment by intelligently synthesizing the best of methodology (confirmatory factor analysis) with the best of theory (Cattell–Horn–Carroll). The Weiss et al. articles represent sophisticated approaches to test validation and interpretation and the commentaries deal with applications, extensions, and limitations of the findings. This “response to the respondents” focuses on Wechsler’s approach to assessment, historical antecedents of factor analysis (especially the contributions of Jacob Cohen in the 1950s), and the “intelligent testing” model of test interpretation.

Measuring Components of Intelligence

The two studies conducted by Weiss, Keith, Zhu, and Chen in 2013 on the Wechsler Adult Intelligence Scale (WAIS-IV) and the Wechsler Intelligence Scale for Children (WISC-IV), respectively, provide strong evidence for the validity of a four-factor solution corresponding to the current hierarchical model of both scales. These analyses support the calculation of the four index scores and the Full Scale IQ. In this article, we discuss some limits of these validation efforts: (a) the incomplete measurement of the construct, (b) the problem of correspondence between factors and broad abilities, (c) the gap between a structural model and a functional model of intelligence, and (d) the difficulty of combining the measurement of global intelligence and broad abilities. Finally, the option of a five-factor model underlying the index scores is analyzed and its potential for future Wechsler scales is discussed.

An Introduction to the Wechsler Intelligence Tests

This special issue focuses on two lead articles examining the factor structure of the fourth editions of the Wechsler Adult Intelligence Scales (WAIS-IV; Wechsler, 2003) and the Wechsler Intelligence Scales for Children (WISC-IV; Wechsler, 2008). These articles are followed by 9 commentaries and a final response by the authors of the lead articles. These diverse approaches critically assess the theoretical and practice implications of the structure of intelligence measured by the Wechsler scales.

Theory and Research

The practice of individual assessment has been moving toward the empirically derived Cattell–Horn–Carroll (CHC) theory of intellectual ability, which offers a hierarchical taxonomy of cognitive abilities. Current assessment tools provide varying adherence to operationalizing CHC theory, making clinical inference difficult. Expert consensus explicating the factors of contemporary tests has proven to be valuable by showing the promise of using a multifactorial assessment of intellectual abilities. The Weiss et al. (2013) articles in this special issue represent the next evolution of this approach by providing empirical research detailing the test factors of the popular Wechsler tests, so that practitioners using those tests can base their clinical inferences on an evidence-based understanding of their measurement tools.

Technical and Practical Issues in the Structure and Clinical Invariance of the Wechsler Scales

This discussion article addresses issues related to expansion of the Wechsler model from four to five factors; multiple broad CHC abilities measured by the Arithmetic subtest; advantages and disadvantages of including complex tasks requiring integration of multiple broad abilities when measuring intelligence; limitations of factor analysis, which constrain test developers to creating specific broad and narrow abilities as opposed to integrative tasks; implications from brain imaging research showing the critical role of neurological pathways that integrate brain regions; close relationship of the fluid reasoning factor to g, and the inadequacies of factor analytically driven statistical definitions of g in the development of improved models of intelligence. In this rejoinder to the commentaries in this special issue on structural models of the WAIS-IV and WISC-IV, the advantages and disadvantages of Schmid–Leiman’s transformation, which removes the effects of g on the broad abilities, and the use of nested or bifactor models in evaluating models of intelligence are also discussed.

The Science of Intelligence Testing

Intelligence has been defined in multiple ways throughout history. In the last 100 years a psychometric approach to define the concept of intelligence has come to dominate the concept. This Commentary provides a brief overview of the history and concepts of intelligence with an emphasis on intellectual assessment. Particular focus is placed on the last 20 years reflecting substantial improvements in the quality of intellectual measures. An argument is made that although confirmatory factor analysis is one way to interpret and understand the Wechsler Scales, another way is to begin with a clearly articulated theory of intellect and to create an instrument designed and validated to fit that theory. Although application of a confirmatory factor analysis to the Wechsler Scales can generate alternate or additional factors that may be interpreted in light of other theories of intelligence such as Cattell-Horn-Carroll (CHC), the opinion is offered that the articles in this issue of JPA offer compelling data that Wechsler’s vision was and is still vibrant and valuable.