In surveying the literature on assessment of cognitive abilities in adults and children, it is easy to assume that the proliferation of test batteries and terminology reflects a poverty of unifying models. However, the lack of recognition accorded good models of cognitive abilities may reflect inattention to theoretical development and injudicious…

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…

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…

The Wechsler Abbreviated Scale of Intelligence, Second Edition (WASI-II; Wechsler, 2011) is a brief intelligence test designed for individuals aged 6 through 90 years. It is a revision of the Wechsler Abbreviated Scale of Intelligence (WASI; Wechsler, 1999). During revision, there were three goals: enhancing the link between the Wechsler…

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…

The authors review the "Advanced Clinical Solutions for WAIS-IV and WMS-IV". The "Advanced Clinical Solutions (ACS) for the Wechsler Adult Intelligence Scale-Fourth Edition" (WAIS-IV; Wechsler, 2008) and the "Wechsler Memory Scale-Fourth Edition" (WMS-IV; Wechsler, 2009) was published by Pearson in 2009. It is a…

Assessment of functional status is an important aspect of clinical evaluation. As part of the standardization of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) and Wechsler Memory Scale-Fourth Edition (WMS-IV), participants completed the Texas Functional Living Scale (TFLS), a measure of Instrumental Activities of Daily Living. The…

The present study examined the factor structure of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV; D. Wechsler, 2008a) standardization sample using exploratory factor analysis, multiple factor extraction criteria, and higher order exploratory factor analysis (J. Schmid & J. M. Leiman, 1957) not included in the WAIS-IV Technical…

The Wechsler Abbreviated Scale of Intelligence, Second Edition (WASI-II; Wechsler, 2011), published by Pearson, is a newly updated abbreviated measure of cognitive intelligence designed for individuals 6 to 90 years of age. Primarily used in clinical, psychoeducational, and research settings, the WASI-II was developed to quickly and accurately…

A measurement model describes both the numerical and theoretical relationship between observed scores and the corresponding latent variables or constructs. Testing a measurement model across groups is required to determine if the tests scores are tapping the same constructs so that the same meaning can be ascribed to the scores. Contemporary tests…

Intellectual assessment is central to the process of diagnosing an intellectual disability and the assessment process needs to be valid and reliable. One fundamental aspect of validity is that of measurement invariance, i.e. that the assessment measures the same thing in different populations. There are reasons to believe that measurement…

This article presents a review of the "Wechsler Adult Intelligence Scale-Fourth Edition" (WAIS-IV), an individually administered measure of cognitive ability for individuals aged 16 years, 0 months to 90 years, 11 months. The WAIS-IV was designed with a number of specific goals including updated norms, increased user friendliness,…

According to the most widely accepted Cattell-Horn-Carroll (CHC) model of intelligence measurement, each subtest score of the Wechsler Intelligence Scale for Adults (3rd ed.; WAIS-III) should reflect both 1st- and 2nd-order factors (i.e., 4 or 5 broad abilities and 1 general factor). To disentangle the contribution of each factor, we applied a…

The use of accommodations for both instruction and assessment continues to be of great importance for students with disabilities. The purpose of this report is to provide an update on the state of the research on testing accommodations, as well as to identify promising areas of research likely to contribute to understanding of current and emerging…

The WAIS III was administered to 16 adults with high functioning autism (HFA) and 27 adults with Asperger syndrome. Differences between Verbal Intelligence (VIQ) and Performance Intelligence (PIQ) were not found. Processing Speed problems in people with HFA appeared. At the subtest level, the Asperger syndrome group performed weak on Digit Span.…