Assessing Adolescent and Adult Intelligence Third Edition Alan S. Kaufman Elizabeth O. Lichtenberger JOHN WILEY & SONS, INC fm.fm Page i Thursday, May 5, 2005 1:49 PM This book is printed on acid-free paper. ∞ Copyright © 2002, 2006 by John Wiley & Sons, Inc. All rights reserved Published by John Wiley & Sons, Inc., Hoboken, New Jersey Published simultaneously in Canada No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. 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Ho tante cose che ti voglio dire, So many things to tell you, o una sola, but really just one, ma grande come il mare, that is as huge as the ocean, come il mare profonda ed infinita. and as deep and infinite. Sei il mio amor e tutta la mia vita. You are my love and my whole life. RODOLFO: O mia bella Mimi! My beautiful Mimi! MIMI: Son bella ancora? Am I still beautiful? RODOLFO: Bella come un’aurora. Beautiful as the dawn in Springtime. A. S. K. For Mike, for everything For everyone on this earth, there will always be one special someone to love. For me, there will always be You. E. O. L. fm.fm Page iii Thursday, May 5, 2005 1:49 PM v Preface to the Third Edition xix PART I Introduction to the Assessment of Adolescent and Adult Intelligence CHAPTER 1 IQ Tests: Their History, Use, Validity, and Intelligent Interpretation 1 Outline of the Book 2 Wechsler’s Scales 3 Clinical Relevance of Theory 3 A Short History of IQ Tests 3 The Binet-Simon Scales 4 Terman’s Stanford-Binet 4 The World War I Tests 5 Wechsler’s Creativity 6 Surveys of Test Usage for Adults 7 Has Test Use Changed over the Years? 8 Test Usage of 1,500 Psychologists and Neuropsychologists 8 How Frequently Are Tests Used? 9 Administration Time and Implications for Reimbursement 10 For What Purposes Are Adults Given Intelligence Tests? 10 Conclusions 10 Validity of the IQ Construct for Adolescents and Adults 11 Prediction of Academic Achievement 12 Relationship of IQ to Education 13 IQ and Occupation 14 Prediction of Job Performance 16 The Intelligent Testing Philosophy 18 IQ Tasks Measure What the Individual Has Learned 19 IQ Tasks Are Samples of Behavior and Are Not Exhaustive 19 C O N T E N T S fm.fm Page v Thursday, May 5, 2005 1:49 PM vi CONTENTS IQ Tasks Like the WAIS-III, KAIT, and WJ III Assess Mental Functioning under Fixed Experimental Conditions 20 IQ Tasks are Optimally Useful When They Are Interpreted from an Information-Processing Model 20 Hypotheses Generated from IQ Test Profiles Should Be Supported with Data from Multiple Sources 21 Tying Together the Tenets of Intelligent Testing 22 Summary 22 CHAPTER 2 Heritability and Malleability of IQ and Attacks on the IQ Construct 24 The Heritability and Malleability of IQ 24 Heritability 24 Maternal Environment 33 Overview 35 Malleability 36 The Flynn Effect 37 The Abecedarian Project 42 Overview of Malleability of IQ 45 Attacks on the IQ Construct 46 Lezak’s Eulogy 46 The Learning Disabilities Challenge 53 Summary 59 CHAPTER 3 From the Wechsler-Bellevue I to the WAIS-III 61 Selection of the Subtests 62 Verbal Scale 62 Performance Scale 66 Item Content Changes from the W-B I to the WAIS to the WAIS-R and to the WAIS-III 69 Reliability Comparisons of the W-B I, WAIS, WAIS-R, and WAIS-III 72 Standardization of the W-B I, WAIS, WAIS-R, and WAIS-III 74 Comparison of the Construct Validity of the W-B I, WAIS, WAIS-R, and WAIS-III 76 Internal Consistency 76 Factor Analysis 78 Developmental Trends 80 Problems with Adolescent Data 82 Clinical Implications of the WAIS-III Norms at Ages 16–19 84 Overview of Developmental Trends 84 Correlations between the W-B I and WAIS, WAIS and WAIS-R, and the WAIS-R and WAIS-III 84 fm.fm Page vi Thursday, May 5, 2005 1:49 PM CONTENTS vii Relationship of the W-B I and WAIS 85 Relationship of the WAIS to WAIS-R 85 Relationship of the WAIS-R to WAIS-III 87 Comparison of Systems for Classifying Intelligence on the W-B I, WAIS, and WAIS-III 87 Comparison of IQs Yielded by the WAIS-R and WAIS-III 89 Practical Implications of WAIS-R/WAIS-III IQ Differences 90 Generalization from the W-B I, WAIS, and WAIS-R to the WAIS-III 91 Studies at Ages 16–19 Years 91 Studies Focusing on Picture Completion, Picture Arrangement, or Object Assembly 91 Factor Analysis Studies 92 Short Form Studies 92 Correlational Studies 93 Group versus Individual Interpretation 93 Conclusions 93 Summary 94 PART II Individual Differences on Age, Socioeconomic Status, and Other Key Variables CHAPTER 4 Individual Differences for Adolescents and Adults on Gender, Ethnicity, Urban–Rural Residence, and Socioeconomic Status 96 Gender Differences 96 Global Scales 96 Gender Differences on Separate Subtests 98 Clinical Implications of Gender Differences on Mental Tasks 100 Ethnic Differences in IQ 101 Differences between Caucasians and African Americans 101 Differences between Caucasians and Hispanics 106 Urban–Rural Residence Differences 109 Generational Changes in Urban–Rural Differences 109 Residence Differences on the WAIS-R Subtests 110 Occupational Differences 111 Best Estimate of IQ Differences for Adults in Different Occupations 111 IQ Variability within Occupational Groups 113 Occupational Status and Canonical Factors 115 Educational Attainment 115 fm.fm Page vii Thursday, May 5, 2005 1:49 PM viii CONTENTS WAIS-III Mean Scores Earned by Adults Differing in Educational Attainment 115 WAIS-III Correlations with Educational Attainment 117 Relationship of Intelligence to Education on the Kaufman Tests 120 Clinical Implications of Educational Data 123 Summary 124 CHAPTER 5 Age and Intelligence across the Adult Life Span 127 Does IQ Decline with Advancing Age? A Cross-Sectional Approach 128 Cross-Sectional Investigations of Wechsler’s Adult Scales 129 Cross-Sectional Investigations of Kaufman and Kaufman’s Adult Tests 150 Overview of Cross-Sectional Investigations 159 Cautions Associated with Cross-Sectional Investigations 161 Does IQ Decline with Advancing Age? A Longitudinal Approach 163 Problems in Investigating Aging Longitudinally 163 Two Groundbreaking Longitudinal Investigations of IQ and Aging 167 Kaufman’s (1990, 2001) Longitudinal Investigations of Wechsler’s Adult Scales Using Independent Samples 171 Interpretation of the Aging Patterns for V-IQ versus P-IQ: Speed or Fluid/Crystallized Ability? 180 Age-Related Declines on Untimed Tasks such as Matrix Reasoning 181 Age-Related Changes on Wechsler’s Arithmetic, Picture Completion, and Picture Arrangement Subtests 181 Data from the Bonn Longitudinal Study 182 Speed versus Cognitive Ability on Digit Symbol 182 Creative Works 182 Integration of Speed, Fluid Ability, and Other Factors 183 Can Cognitive Decline Be Slowed Down? 187 Summary 189 PART III Integration and Application of WAIS-III Research CHAPTER 6 Research on Administration, Scoring, and Relationships between Wechsler Scales 192 Administration and Scoring 192 Administration Time 192 Administration Errors 197 fm.fm Page viii Thursday, May 5, 2005 1:49 PM CONTENTS ix The Nature and Frequency of Administration Errors 197 Scoring Errors 198 Implications for Administering and Scoring the WAIS-III 202 WAIS-III Stability 202 WAIS-III Test-Retest Reliability and Practice Effects 202 Alternate Forms Reliability and Stability: WAIS-III versus WISC-III 209 Summary 216 CHAPTER 7 Factor Analysis of the WAIS-III 218 The WAIS-III as a One-Factor Test 218 The WAIS-III as a Two-Factor Test 220 The WAIS-III as a Three-Factor Test 222 The WAIS-III as a Four-Factor Test 223 How Many Factors Underlie the WAIS-III? 224 Are There Two, Three, or Four WAIS-III Factors? 225 Differences in WAIS-III Factor Structure Due to Ethnicity 227 Age Differences in the WAIS-III Factor Structure 227 Comparison of WAIS-III and WAIS-R Factors 232 Comparison of WAIS-III and WISC-III Factors 232 The General Factor (g) 234 Subtest Specificity 235 Definition of Subtest Specificity 236 Subtest Specificity of WAIS-III Subtests 236 Evaluation of the WAIS-III 237 Groth-Marnet, Gallagher, Hale, and Kaplan (2000) 237 Kaufman and Lichtenberger (1999) 242 Sattler and Ryan (1999) 242 Summary 243 CHAPTER 8 Verbal–Performance IQ Discrepancies: A Neuropsychological Approach 244 V–P Discrepancies and Brain Damage 244 Right- versus Left-Brain Lesions 245 Wechsler-Bellevue Studies 251 WAIS Studies 251 Overlapping Samples of Patients 252 WAIS-R Studies 252 Comparison of Results for Wechsler-Bellevue versus WAIS versus WAIS-R 252 Todd, Coolidge, and Satz’s Large-Scale Study with the WAIS 253 fm.fm Page ix Thursday, May 5, 2005 1:49 PM x CONTENTS Smith’s Large-Scale Investigations Using the Wechsler-Bellevue 253 Bilateral Brain Damage 254 General Conclusions regarding Studies of Brain Damage 257 The Nature of Brain Damage 258 Lesions Caused by Stroke, Head Injury, and Tumors 259 Temporal Lobe Epilepsy 263 Temporal Lobe versus Parietal Lobe Lesions 266 Frontal Lobe Lesions 266 Frontal versus Posterior Lesions 266 Acute versus Chronic Lesions 267 Fitzhugh et al.’s Study 267 Aggregated Data from Several Samples 268 Correlational Studies 269 Subtest Patterns for Left- and Right-Lesion Patients 269 Mean Scaled Scores for Patients with Focal Brain Damage 269 Discrimination between Right- and Left-Lesion Patients 270 Hemispheric Functioning: Process versus Content 274 Should V–P Discrepancies Be Used for Assessing Brain Damage? 275 Gender of Patients with Lateralized Lesions 276 Lansdell’s Initial Observations 276 McGlone’s Research 277 Well-Controlled Investigations 278 Inglis and Lawson’s Study of Gender Differences 278 Turkheimer et al.’s Study of Gender Differences 278 Inglis and Lawson’s Meta-Analysis of Gender Difference Studies 279 Bornstein and Matarazzo’s Review of Gender Difference Studies 279 Snow, Freedman, and Ford’s Review of Gender Differences 280 Turkheimer and Farace’s Meta-Analysis of Gender Difference Studies 281 Research Issues in the Investigation of Gender Differences 283 Aggregated Data from Gender Difference Studies 283 Proposed Explanations of the Interaction with Gender 284 Summary of Evaluation of Hypotheses for Gender Differences in Lesioned Patients 292 Ethnicity of Patients with Lateralized Lesions 293 Munder’s Careful Investigation of V–P Differences for Caucasians and African Americans 293 Subtest Patterns for Brain-Damaged Males by Race 294 Age of Patient Samples 296 Brain Damage in Children and in Adults 296 Empirical Analysis with Samples of Adolescents and Adults 297 Educational Level of Patient Samples 297 fm.fm Page x Thursday, May 5, 2005 1:49 PM CONTENTS xi Research Implications of Base-Rate Education Data 299 Education Level and V–P for Brain-Damaged Samples 300 Education as a Variable for Normal versus Brain-Damaged People 300 Clinical Issues in the Interpretation of a Patient’s V-P Difference 302 Individual versus Group Data 303 Emotional Disturbance and Diffuse Brain Injury 304 Emotional Disturbance and Lateralized Lesions 304 V–P Interpretation in the Context of Patients’ Behaviors 307 Illustrative Case Report 308 Walt H., Age 21, Head Injury 308 Summary 314 CHAPTER 9 Verbal–Performance IQ Discrepancies: A Clinical Approach 317 Variables Believed to Be Correlates of High Performance IQ 317 Learning Disabilities 318 Delinquency and Psychopathic Behavior 327 Bilingualism 330 Autism 332 Mental Retardation 334 Overview of Variables Believed to Be Correlates of High Performance IQ 337 Variables Believed to Be Correlates of High Verbal IQ 337 Psychiatric Disorders 338 Alcohol Abuse 340 Motor Coordination Problems 341 Alzheimer’s-Type Dementia 344 High Average and Gifted Intellectual Functioning (Full Scale IQ of 110+) 350 Overview of Variables Believed to Be Correlates of High Verbal IQ 353 When V–P IQ Discrepancies Are Meaningless 354 IQs Are Not Unitary Constructs 354 Verbal Compensation for Performance Deficit 355 Effects of Retesting 356 Illustrative Case Reports 357 Chester P., Age 17, Possible Autism 357 Robert N., Age 36, Mild Retardation 362 Summary 366 fm.fm Page xi Thursday, May 5, 2005 1:49 PM