There has been insufficient effort in most areas of applied psychology to evaluate incremental validity. To further this kind of validity research, the authors examined applicable research designs, including those to assess the incremental validity of test instruments, of test-informed clinical inferences, and of newly developed measures. The authors also considered key statistical and measurement issues that can influence incremental validity findings, including the entry order of predictor variables, how to interpret the size of a validity increment, and possible artifactual effects in the criteria selected for incremental validity research. The authors concluded by suggesting steps for building a cumulative research base concerning incremental validity and by describing challenges associated with applying nomothetic research findings to individual clinical cases.

https://psycnet.apa.org/journals/pas/15/4/446.pdf

The incremental validity of psychological testing and assessment: conceptual, methodological, and statistical issues.

This study employed observed factor index scores as well as latent ability constructs from the Wechsler Intelligence Scale for Children—Fourth Edition (WISC-IV; Wechsler, 2003) in estimating reading and mathematics achievement on the Wechsler Individual Achievement Test—Second Edition (WIAT-II; Wechsler, 2002). Participants were the nationally stratified linking sample (N = 498) of the WISC-IV and WIAT-II. Observed scores from the WISC-IV were analyzed using hierarchical multiple regression analysis. Although the factor index scores provided a statistically significant increment over the Full Scale IQ, the size of the improvement was too small to be of clinical utility. Observed WISC-IV subtest scores were also subjected to structural equation modeling (SEM) analyses. Subtest scores from the WISC-IV were fit to a general factor (g) and four ability constructs corresponding to factor indexes from the WISC-IV (Verbal Comprehension, Perceptual Reasoning, Working Memory, and Processing Speed). For both readin...

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Distinctions Without a Difference The Utility of Observed Versus Latent Factors From the WISC-IV in Estimating Reading and Math Achievement on the WIAT-II

Learning Behavior and Intelligence as Explanations for Children's Scholastic Achievement

Intelligence Testing: Status and Trends.

Interpretation of intelligence tests involves making various inferences about the individual based on their performance. Because there are many different scores within intelligence tests reflecting different levels (Full Scale, factors, subtests) and there are many different comparisons provided in test manuals and the extant literature, there is a multitude of possible inferences. This chapter is concerned with reviewing the various available scores and comparisons with suggested interpretations and a review of the empirical investigations of their psychometric fitness (reliability, validity, utility). Differentiation of psychometric interpretation versus actuarial interpretation methods is presented, as well as a review of research related to each. Most intelligence test interpretation methods are considered psychometric in nature, and most lack sufficient reliability, validity, or utility for individual clinical use; improvements in the clinical assessment of intelligence may result from greater development and use of actuarial approaches.

Psychometric Versus Actuarial Interpretation of Intelligence and Related Aptitude Batteries

When the Kaufman Assessment Battery for Children (K-ABC ; A. S. Kaufman & N. L. Kaufman, 1983a, 1983b) was published just over 10 years ago, it had many unique features, including its information processing model and specific recommendations for educational remediation. Although the test has received much attention because of these characteristics, the K-ABC has also been the subject of much controversy. Through consideration of some of these arguments, lessons that researchers in the field of child assessment may learn from the K-ABC and their implications for future directions are identified. Based in part on lessons learned from the K-ABC, an alternative assessment model for the evaluation of children with reading problems is proposed at the end of this article.

Lessons From the Kaufman Assessment Battery for Children (K-ABC): Toward a New Cognitive Assessment Model

Scatter analysis of IQ profiles has a long and controversial history. We conducted this study to determine whether the validity of scatter information is any greater for 2 new IQ batteries, the Kaufman Assessment Battery for Children (K-ABC) and the Fourth Edition Stanford-Binet (SB4), than for the Wechsler Intelligence Scale for Children-Revised (WISC-R). Within a sample of referred children, we computed numerical indexes of profile elevation, shape, and variability for all IQ tests. Using hierarchical multiple regression with achievement scores as dependent variables, we found shape information had marginal incremental validity over elevation as a predictor for the WISC-R, even less for the SB4, and virtually none for the K-ABC. We discuss implications of these results.

Relative usefulness of elevation, variability, and shape information from WISC—R, K-ABC, and Fourth Edition Stanford-Binet profiles in predicting achievement.

We evaluated whether abilities measured by the Kaufman Assessment Battery for Children (K-ABC)are as complex as those measured by the Wechsler Intelligence Scale for Children-Revised (WISC-R)within a sample of referred children. Results of factor and multidimensional scaling analyses indicated that abilities tapped by the K-ABC Mental Processing scale are not as complex as those assessed by the WISC-R. K-ABC Achievement scale subtests, however, seemed to assess skills as complex as those measured by many WISC-R subtests. The relative cognitive complexity of the K-ABC and the WISC-R seem comparable, but only when all the K-ABC subtests are administered.

Relative Cognitive Complexity of the Kaufman Assessment Battery for Children (K-ABC) and the WISC-R

R. W. Kamphaus and C. R. Reynolds developed a scoring system for the Kaufman Assessment Battery for Children (K-ABC) in which test users derive alternative summary scores, including General Intelligence, Verbal Intelligence, and Reading composites. In this study, we evaluated the construct validity of this supplementary scoring model with data from a sample of referred school-age children and from the K-ABC normative sample. Within the referred sample, we conducted a factor analysis to determine the joint factor structure of subtests from the K-ABC and other IQ and achievement measures. We evaluated within the normative sample the relative fits of the factor models implied by the original and Kamphaus-Reynolds scoring models to subtest inter-correlations. Our results supported the construct validity of only part of the Kamphaus-Reynolds scoring model.

Joseph Snyder

Papers

Lessons From the Kaufman Assessment Battery for Children (K-ABC): Toward a New Cognitive Assessment Model

Relative usefulness of elevation, variability, and shape information from WISC—R, K-ABC, and Fourth Edition Stanford-Binet profiles in predicting achievement.

Relative Cognitive Complexity of the Kaufman Assessment Battery for Children (K-ABC) and the WISC-R

Evaluation of the Construct Validity of the Kamphaus-Reynolds Supplementary Scoring System for the K-ABC