This is an edited collection of papers that focuses on various aspects of the most recent revision of the Wechsler Adult Intelligence Scale (WAIS–III) and Wechsler Memory Scale (WMS–III). The papers in this volume fall into three broad areas. The first section of the book (and part of one of the subsequent chapters) provides an overview of the history of the development of measures of memory and intelligence, with particular emphasis on the Wechsler scales. These chapters are thoroughly delightful, and the only shortcoming is that they are too brief. Indeed, though over 100 pages are devoted to this topic, there are a number of questions about the measures which could have been answered but weren't. (For example, given the cost and time pressures on psychological assessment, why were the tests—particularly the WMS–III—lengthened? Why, for example, include a measure of list learning when Psychological Corporation already published the California Verbal Learning Test? Why, after all these years, hasn't the WAIS Information subtest been dropped or the content made less specific to the United States? What led to the decision to include a verbally mediated measure of visual memory on the WMS–III, a decision which can make it harder to evaluate visual memory in aphasics?) Given how involved they were in the revisions of the WAIS and WMS, the editors would appear to have been uniquely positioned to provide a more in-depth discussion of the issues that arose during this process and how these issues were resolved.

The chapters in the final section of the book focus on clinically relevant topics such as assessment of populations with specific disabilities, assessment of non-native English speakers, and how to train others in the administration of the tests. Much of this material will be familiar to experienced clinicians, but these chapters would serve as a useful adjunct to any graduate-level testing course. (Indeed one of the particular additional strengths of this book is that it is a rich source of topics for dissertation research).

The heart of the book is the middle section, which focuses on a specific, factor-analytically based approach to test interpretation. (Hence, the title of the book is somewhat misleading. It is not, strictly speaking, about the clinical interpretation of either the WAIS-III or the WMS–III, but primarily about a modification to the traditional index structure.) Part of the impetus for the development of the present model appears to stem from an error discovered in the original factor analysis of the WMS–III. Though the original factor analysis suggested a five-factor model, reanalysis indicated that a three-factor model accurately represented the factor structure of the WMS–III. Building in part on this work, and with some apparent influence from the Mayo Older Americans Normative Studies, the present book devotes much of its attention to a six-factor model for the combination of the WAIS and WMS subtests: the Verbal Comprehension, Perceptual Organization, and Processing Speed Index Scores from the WAIS-III, the Working Memory Index from the WMS–III, and two new Memory Index Scores (Auditory and Visual Memory Composite Index Scores). Because the six-factor model yielded no separate factor for delayed recall—either verbal or visual, the authors have grafted on what appear to be some ad hoc indexes in an attempt to allow a separate analysis of delayed verbal and visual recall.

Having developed the model in chapter 4, the authors then provide useful additional information about demographic corrections, base rates of discrepancy scores, diagnostic utility, and reliable change scores in subsequent chapters. They also discuss the effects on the factor structures of substituting or omitting some subtests.

A book review cannot do justice to this model, nor can it cover all of the complexities of the analyses undertaken by the authors. One obvious potential benefit of the six-factor model is that it permits assessment of each of the key Index scores with fewer total tests (and test time) than does administration of the complete WAIS/WMS. This benefit is not without cost, however. For example, Arithmetic (which has, perhaps, more ecological relevance than some subtests) is optional. Similarly, Digit Span, which can be used for assessing effort as well as attention, is also optional. In addition, while decreasing the number of tests required for mapping the cognitive domains of relevance, the psychologist's computational burden is increased, since the new Memory Indexes are not included in the current version of Psychological Corporation's scoring software.

The proposed model also suffers from one of the typical drawbacks of factor analysis—focus on the statistical with little emphasis on the practical. For example, while some neuropsychologists are still interested in making inferences about localization of damage the present work is largely silent on that issue. There is a chapter on the diagnostic utility of the new model, but the data presented concentrates on the diagnostic groups presented in the test manual. (Given how small—and selective—the patient samples in the manual are, it is hard to demonstrate whether the six-factor model is superior to the traditional approach). Finally, it remains to be determined if the present model will represent a significant improvement over the approaches we are currently using when it comes to predicting behavior in the real world. Indeed, once we have accounted for the predictions we can make on the basis of g, how much benefit do we get out of the data from any of the other factors?

Ultimately, the utility of the six-factor model will depend on whether it answers questions more expeditiously than the full WAIS–III/WMS–III and more thoroughly than the Wechsler Abbreviated Scale of Intelligence (WASI) and the Wechsler Memory Scale–Abbreviated (WMS–III–A). The model deserves further consideration and one can only hope that the Psychological Corporation will expedite the necessary modifications to the scoring software to permit interested psychologists to compare this model with the current Index and IQ scores.

As a final comment, although much of this book focuses on one particular approach to organizing the data from the WAIS and WMS, these chapters deal with larger issues which are not specific to the six-factor model. A reader who is satisfied with the current Index and IQ scores will nevertheless find much that is thought-provoking, clinically useful, and insightful.