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Copyright © 2002 by The Psychological Corporation. All rights reserved.Copyright © 2004 by Harcourt Assessment Inc. All Rights Reserved

Copyright © 2004 by Harcourt Assessment, Inc. All Rights Reserved

Wechsler Scales and Revisions

WISC-IV2003

WISC-IV2003

W-B 1939

WAIS 1955

WAIS–R 1981

WAIS–III 1997

W-B II 1946

WISC 1949

WISC–R 1974

WISC–III 1991

WPPSI 1967

WPPSI–R 1989

WPPSI–III 2002


WISC–IVThe KIT

Administration ManualTechnical ManualStimulus Book (9" X 6")BlocksSymbol Search/Coding

BookletCancellation BookletRecord Form

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Where Could We Be Going?

1. Elimination of the Ability-Achievement Discrepancy

2. Emphasizing Cognitive Processing Information provided by the IQ Test

3. Replacement of the traditional “Wait to Fail” model

4. Increase in focus on Pre-referral Assessment and Intervention

5. Changing of the definition of Learning Disability


Revision Goals

Update & Strengthen Theoretical FoundationsEnhance Clinical UtilityImprove Psychometric PropertiesIncrease and Enhancing User-FriendlinessMaintain Continuity and Familiarity


Update & Strengthen Theoretical Foundations

Current Status of Intelligence Theory• Use of Factor Index Scores

Emphasizes multiple factors in cognitive abilities De-emphasizes reliance on VIQ and PIQ to characterize a child’s overall cognitive abilities

• Consistent with WPPSI-III and WAIS-III• Enhanced Measures of Fluid Reasoning

Tasks that involve “manipulating abstractions, rules, generalizations, and logical relationships” require fluid intelligence (Carroll, 1993, p. 583). MR, PCO, and WR developed to enhance the measures of fluid intelligence

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Update & StrengthenTheoretical Foundations

• Enhanced Measures of Working MemoryEmphasizes the importance of working memory in learning Focuses on more “active” types of working memory

• Enhanced Measures of Processing SpeedTargets role as “mediator” in cognitive functioning and learningRecognizes impact as predictor of reading comprehension


Enhanced Clinical Utility

Increasing Number of Special Group Validity StudiesUpdating Statistical Linkage to

Other Cognitive Measures and Measures of Achievement


Enhancing Clinical Utility

• Mental Retardation – Mild• Mental Retardation – Moderate• Learning Disorder – Reading• Learning Disorder – Reading,

Writing• Learning Disorder – Reading,

Writing, and Math• Learning Disorder – Math• Receptive Language Disorder• Receptive/Expressive Language

Disorder

• ADHD• ADHD/LD Combined• Motor Impaired• Autism/Aspergers• TBI – Open• TBI – Closed• Intellectually Gifted

Increased and Enhanced Clinical Validity Studies

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Enhancing Clinical Utility

Increased Linkage and Correlations with Other Assessments

Equivalency studies with WISC-III, WAIS-III, WPPSI-III, WASI, approximately 200 cases each, counterbalancedWIAT-II Link, 550 casesCMS Link, 110 cases Adaptive Behavior Assessment System (ABAS) Link, 200 cases each for Parent/Teacher formsBar-ON EQ, 200 casesGifted Rating Scale, 240 cases


Improved Psychometric Properties

Updating NormsImproving Evidence of Reliabilityand Validity

Extending Floors and CeilingsRe-examining Item Bias


Increased User-Friendliness

Decreasing Testing TimeSimplifying Administration and Scoring ProceduresImproving Stimulus MaterialsEliminating the Object Assembly subtestDividing and Reorganizing the ManualDividing and Reorganizing the Record Form

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Reasons for Updating Norms

Improvement in Education SystemImproved nutritionBetter health conditionsIncreased dissemination of information

Demographic shifts• Hispanic population growth (11% to 15%)• Regional growth (Growth in West and South

at the expense of NE)

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Basic Description of Basic Description of the New WISCthe New WISC––IVIV


WISC–IV Model

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Basic Description of the WISC–IV

Individual AdministrationAssessment of Cognitive Functioning in Children 6–16 Years• 10 Subtests to obtain FSIQ• 10 Subtests to obtain Index Scores• 3 Core Verbal and 3 Core Perceptual Reasoning

Subtests• 2 Core Working Memory and 2 Core Processing

Speed SubtestsAdministration time: median = 67 minutes


Verbal Comprehension Index

Core Subtests:• Similarities• Vocabulary • Comprehension

Supplementary Subtests:• Information• Word Reasoning


Perceptual Reasoning Index

Core Subtests:• Block Design• Picture Concepts• Matrix Reasoning

Supplementary Subtest:• Picture Completion

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Working Memory Index

Core Subtests:• Digit Span• Letter-Number Sequencing

Supplementary Subtest:• Arithmetic


Processing Speed Index

Core Subtests:• Coding• Symbol Search

Supplementary Subtest:• Cancellation


Order of WISC-IV Subtests

Core SubtestsBlock DesignSimilaritiesDigit SpanPicture ConceptsCoding VocabularyLetter – Number SequencingMatrix ReasoningComprehension Symbol Search

Supplemental Subtests11. Picture Completion12. Cancellation13. Information14. Arithmetic15. Word Reasoning

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Block Design

14 items—two parts• 3 new items designed to

improve ceiling and item difficulty gradient

• No time-bonus administration option


Block Design

Any pronounced rotation of 30o or more is considered an error.

Correct only the first rotation that occurs by rotating the blocks to the correct position andsaying, “See, it goes this way.” Continue subtest administration accordingly.


Block Design

Designed to measure the ability to analyze and synthesize abstract visual stimuli and nonverbal concept formation.Involves nonverbal fluid reasoning, visual perception and organization, visual-motor coordination, spatial visualization, and the ability to separate figure and ground in visual stimuli.

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Similarities

Core Subtest23 items• 11 new items–Scoring criteria modified• Practice items reduced from 5 to 2

“In what way are RED and BLUE alike?”


Similarities

Designed to measure fluid verbal reasoning and concept formation.

Also involves auditory comprehension, memory, distinguishing non-essential and essential features, and verbal expression.


Digit Span

Digit Span Forward requires the child to repeat numbers in the same order the examiner reads aloud.Digit Span Backward requires the child to repeat the numbers in the reverse order presented by the examiner.

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Digit Span

Designed as a measure of working memory (initial encoding & mental manipulation), auditory short-term memory, sequencing skills, attention, and concentration.Digit Span Forward involves initial encoding, attention,and auditory processing.Digit Span Backward involves mental manipulation, transformation of information, and visuospatial imaging.Shift from the Forward to the Backward task requires cognitive flexibility and mental alertness.


Picture Concepts

28 items–The child is presented with two or three rows of pictures and chooses one picture from each row to form a group with a common characteristic.


Picture Concepts

Designed to measure abstract, fluid, and categorical reasoning ability.Solutions to easier items are generally attained by reasoning based on concrete representations, and the solutions to more difficult items are obtained by reasoning based on more abstract representations.

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Coding

Measures processing speed

Involves short-term memory, learning ability, visual perception, visual-motor coordination, visual scanning ability, cognitive flexibility, attention, motivation and visual and sequential processing.


Vocabulary

36 items• 4 picture items designed to extend the floor of

the subtest.• 32 verbal items—5 new items to improve item

difficulty gradient. Scoring modifications onall items.

“What is a car?”


Vocabulary

Designed to assess a child’s word knowledge and degree of language development. Also designed to measure a child’s fund of knowledge, learning ability, long-term memory, and verbal concept formation.Other abilities that may be utilized include auditory perception and comprehension, verbal conceptualization, abstract thinking, and verbal expression.

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Letter-Number Sequencing

Measures Working MemoryAdapted from the WAIS–IIIChild is presented a series of numbers and letters. The child repeats numbers then letters in order.Involves sequencing, mental manipulation, attention, short-term auditory memory, visuospatial imaging, and processing speed.


Letter-Number Sequencing

Example:

Examiner says, “7 K 3 D 9”

Child responds, “3 7 9 D K”


Definitions of Fluid Reasoning

It is the “ability to perform mental operations, such as the manipulation of abstract symbols”

Sternberg, 1995It is Gf from the Horn–Catell model

Catell, 1941; Horn, 1968It encompasses the abilities of reasoning under novel conditions: general reasoning, figural relations, semantic relations, classifications, concept formation.

Horn & Noll, 1997

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Matrix Reasoning

35 items—child completes matrices from five response options.


Matrix Reasoning

Measure of fluid intelligence and a reliable estimate of general intellectual ability.Four types of matrices including: continuous and discrete pattern completion, classification, analogical reasoning, and serial reasoning.


Comprehension

21 items—all items require the child to answer questions.11 new items and 10 items retained.

“Why do people brush their teeth?”

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Comprehension

Measures verbal reasoning and conceptualization, the ability to evaluate and utilize past experiences, verbal comprehension and expression, and the ability to demonstrate practical information.Involves knowledge of conventional standards of behavior, social judgment, maturity, and common sense.


Symbol Search

Nonverbal Measure of Processing SpeedUses abstract symbols2 target symbols per item5 search symbols per itemEqual difficulty across all itemsDifficulty range from .85 to 1.0


Symbol Search

Involves processing speed, short-term visual memory, visual-motor coordination, cognitive flexibility, visual discrimination, and concentration.May also tap auditory comprehension, perceptual organization, and planningand learning ability.

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Picture Completion

38 items—all artwork has been redrawn, enlarged and colorized.25 items retained,

13 new items to improve difficulty gradient.


Picture Completion

Now a Supplemental Subtest.

Measures visual perception and organization, concentration, and visual recognition of essential details of objects.


Cancellation

Supplemental Subtest Measure of Processing Speed2 forms (Random, Structured)Forms share identical target locations.Targets are animals.Foils are common, non-animal objects.

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Random vs. Structured(Targets in same location)

Measures processing speed, visual selective attention, vigilance, and visual neglect.


Information

33 items• 11 new verbal items—22 retained

from WISC–III. Some scoring modifications.

“Show me your foot.”


Information

Designed to assess a child’s ability to acquire, retain, and retrieve general factual knowledge, commonly referred to as general fund of knowledge.Involves crystallized intelligence, long-term memory, and the ability to retain and retrieve knowledge from school and environment. Also involves auditory perception and comprehension and verbal expressive ability.

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Arithmetic

Supplemental Working Memory SubtestThe child mentally solves a series of orally presented arithmetic problems within a specified time limit.

“Count these birds with your finger. Count them out loud so I can hear you.”


Arithmetic

Involves mental manipulation, concentration, attention, short- and long-term memory, numerical reasoning ability, and mental alertness. May also involve sequencing, fluid reasoning, and logical reasoning.


Word Reasoning

24 items—Examiner reads increasingly specific series of one to three clues and the child is asked to identify the common object or concept.

“Tell me what I’m thinking of. This is an animal that goes ‘woof.’ What is it?”

“Tell me what I’m thinking of.1. This has a long handle…2. and is used with water to clean the floor.

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Word Reasoning

Measures verbal deductive reasoning.Skills that contribute to success include verbal comprehension, expressive language ability, verbal abstraction, domain knowledge, analogic and general reasoning, ability to utilize contextual and syntax information, generate alternative concepts, and integrate and synthesize different types of information.Other contributing skills include long-term memory, cognitive flexibility, and trial-and-error learning.

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Technical Developmentand Standardization


Review of WISC–III Item DevelopmentAdvisory Panel and Clinical ConsultantsFocus Groups and Telephone SurveysSurveys of Experts and ExaminersPilot StageTryout StageStandardization StageFinal Assembly and Evaluation

Phases of Conceptual Development

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Demographic Stratification Variables

AgeSexRace/Ethnicity Parent Education LevelGeographic Region


Stratification Variables: Age

6:00 -

6:11

7:00-

7:11

8:00-

8:11

9:00-

9:11

10:00-

10:11

11:00-

11:11

13:00-

13:11

14:00-

14:11

WISC- IV 200 200 200 200 200 200 200 200 200

12:00-

12:11

15:00-

15:11

16:00-

16:11

200 200


Stratification Variables: Sex

Age GroupAge Group

Female n = 1100; Male n = 1100

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Stratification Variables: Race/Ethnicity


Stratification Variables: ParentEducation Level


Stratification Variables: Geographic Region

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Exclusionary Criteria for Standardization Sample


Additional Sampling Issues

Ethnicity/Bias Oversample during Tryout PhaseEducation Level OversampleValidity Data From Clinical GroupsCorrelational Data From Other TestsTest–Retest Data

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Evidence of Reliability

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Concept of Reliability

Refers to the accuracy, consistency, and stability of test scores across situationsThe difference between the hypothetical true score and the individual’s obtained test score is measurement error.A reliable test will have relatively small measurement error and consistent measurement results within one administration and on different occasions.


Evidence of Internal Consistency

The reliability coefficients for WISC–IV composite scales range from .88 (Processing Speed) to .97 (Full Scale).The average reliability coefficients of the WISC–IV subtests range from .79 (Symbol Search and Cancellation) to .90 (Letter–Number Sequencing). All remaining reliability coefficients range from .80 (Word Reasoning) to .89 (Vocabulary and Matrix Reasoning).


Reliability Coefficients of the Subtests, Process Scores, and Composite Scales, by

Age Group

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Reliability Coefficients of the Subtests and Process Scores for Special Groups


Evidence of Test–Retest Reliability


Evidence of InterscorerReliability

All WISC–IV protocols were double-scored by two independent scorers, and evidence of interscoreragreement was obtained using the normative sample.Because the scoring criteria for most of the subtests are simple and objective, interscorer agreement is very high, ranging from .98 to .99.Total subtest scores were used in the analysis, interscorer reliabilities were .98 for Similarities, .98 for Vocabulary, .95 for Comprehension, .96 for Information, and .97 for Word Reasoning.

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Evidence of Validity


Exploratory Factor Pattern Loadings for Core Subtests


Exploratory Factor Pattern Loadings for Core and Supplemental Subtests

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Clinical Validity Studies


Clinical Linking Studies

Mental Retardation – Mild WISC-IV WISC-IV IntegratedMental Retardation – Moderate

Learning Disorder – ReadingLearning Disorder – Reading, WritingLearning Disorder – Reading, Writing, MathLearning Disorder – Math

WISC-IV WISC-IV Integrated WIAT-II PAL

Receptive Language DisorderReceptive/Expressive Language Disorder

WISC-IV WISC-IV Integrated CELF-4


Clinical Linking Studies

ADHDADHD/LD Combined

WISC-IV WISC-IV Integrated BROWN ADHD

Motor Impaired WISC-IVAutism/Aspergers WISC-IV WISC-IV Integrated

TBI – Open WISC-IV WISC-IV Integrated NEPSY D-KEFSTBI – Closed WISC-IV WISC-IV Integrated NEPSY D-KEFS

Gifted WISC-IV D-KEFS EQ GRS

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The Record Form


Calculating Examinee’s Age

1. Enter Date of Testing in format Year/Month/Day2. Enter Date of Birth in format Year/Month/Day3. Subtract Day, then Month, then Year.

(All months are assumed to have 30 days.)4. DO NOT round up.


Completing the Summary Page

1. Calculate Subtest Total Raw Scores

2. Convert Total Raw Scores to Scaled Scores

3. Obtain Sums of Scaled Scores4. Determine the Composite Scores5. Plot the Score Profiles

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Sample Completed Summary Page


Sample Conversion of Raw Scores to Scaled Scores


Completed Analysis Page

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Completed Analysis Page

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Scoring the WISC––IV


WISC–IV Software Related Information

1. When a WISC–III Scoring Assistant user installs WISC–IV, the WISC–III raw scores window and WISC–III reports will still be available. In other words, WISC–IV is not an upgrade of WISC–III. It is added to the platform as a new and separate product.

2. The WIAT–II Scoring Assistant is automatically updated to perform discrepancy analysis reporting with WISC–IV when WISC–IV is installed. A separate WIAT–II update CD is not necessary.

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Wechsler Software Purchase PlanNew Customers

I HAVE I WANT THIS REPORT CAPABILITY I NEED TO BUY

- WISC-IV Scoring Assistant Reports WISC-IV Scoring Assistant

- WISC-IV & WIAT-II Scoring Assistant Reports

WISC-IV Scoring Assistant and the WIAT-II Scoring Assistant

- WISC-IV Scoring Assistant & Writer Reports WISC-IV Writer

- WISC-IV & WIAT-II Scoring Assistant & Writer Reports

WISC-IV Writer and the WIAT-II Scoring Assistant

- WPPSI-III Scoring Assistant WPPSI-III Scoring Assistant

- WPPSI-III & WIAT-II Scoring Assistant Reports

WPPSI-III Scoring Assistant and the WIAT-II Scoring Assistant

- WPPSI-III & WIAT-II Scoring Assistant & Writer Reports

WPPSI-III Writer and the WIAT-II Scoring Assistant

No Platform Product


Wechsler Software Purchase PlanExisting Customers

I HAVE I WANT THIS REPORT CAPABILITY I NEED TO BUY UPGRADE PRICE?

- WISC-IV & WIAT-II Scoring Assistant Reports WISC-IV Scoring Assistant No

- WISC-IV & WIAT-II Scoring Assistant Reports - WISC-IV & WIAT-II Writer Reports WISC-IV Writer No

- WISC-III & WIAT-II Writer ReportsWISC-III-WIAT-II Upgrade to Writer Yes

- WISC-IV & WIAT-II Scoring Assisant Reports WISC-IV Scoring Assistant No

- WISC-IV & WIAT-II Writer Reports WISC-IV Writer No

- WISC-IV & WIAT-II Scoring Assistant Reports WISC-IV Scoring Assistant No

- WISC-IV & WIAT-II Writer Reports WISC-IV Writer No

- WISC-IV & WIAT-II Scoring Assistant Reports WIAT-II Scoring Assistant No

- WISC-IV Writer Reports WISC-IV Upgrade to Writer Yes

WIAT-II Scoring Assisant

WISC-III-WIAT-II Scoring Assistant

WISC-III-WIAT-II Writer

WISC-IV Scoring Assistant


Software Packaging:A Modular Approach

Future of software on the PsychCorpCenter (PCC) is taking modular approach (one instrument per application)

Allows for ease in maintenance and serviceability

Still allows for report integration across instruments (WISC–IV—WIAT–II, WISC-III—WIAT–II, WPPSI–III—WIAT–II discrepancy analysis)

e.g., Discrepany

Analysis Reporting

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Interpretation


Interpretation of WISC–IV Scores

Subtest Scaled Scores:Mean = 10, SD = 3

IQ and Index Scores:Mean = 100, SD = 15

Individual’s Rank Compared to Normative Group

FSIQ Score: Overall AbilityIndex Scores: Breakdown of AbilitiesSubtest Scores: Strengths and Weaknesses


Enhancement of Clinical Interpretation

Qualitative Descriptions of FSIQ Score and Index Scores

Confidence IntervalsAdditional Tables for Determining

Statistical SignificanceBase Rates for Discrepancy Scores

(Overall and by Ability Level)Age-Corrected Subtest Scaled ScoresDiscrepancies Between Digit Span Forward

and Backward

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Conceptualization Structure

Core Input Requirements• e.g., Hearing, Vision, Motor

Core Processing and Output Requirements • Minimum verbal expression to maximum verbal

expression required.• Minimum motor output required to maximum motor

output required.• Maximum structure and organization provided to

minimum amount of structure and organization required.• Maximum amount of contextual information provided to

minimum amount of contextual information provided.


Conceptualization Structure

Characteristics of Response• Correct, Efficient, and Automatic• Incorrect, Efficient, and Automatic• Correct, Inefficient, and Effortful• Incorrect, Inefficient, and Effortful


Qualitative Descriptions of IQ Scores

Score Classification% Included in Theoretical

Normal Curve

130 and above120–129110–11990–10980–8970–7969 and below

Very SuperiorSuperiorHigh AverageAverageLow AverageBorderlineExtremely Low

2.26.7

16.150.016.16.72.2

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Using the Qualitative Descriptions

Relative to individuals of comparable age, this individual is currently functioning in the [descriptive classification] range on a standardized measure of intelligence.


LNS = DS = A LNS > DS > ASubtests

Example of Subtest Profiles

Index Subtests Index


Patterns and Profiles of Performance

Profile analyses can be used to evaluate scatter within or among FSIQ, Index Scores and Subtests.

Profile analyses can be used to generate hypotheses that are either corroborated or refuted by other evaluation results, such as

background information,direct behavioral observation,additional evaluation,consistency with injury or disorder.

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WISC-IV Levels of Performance

FSIQFSIQFSIQ

Block DesignMatrix ReasoningPicture ConceptsPicture Completion

SimilaritiesVocabularyComprehensionInformationWord Reasoning

CodingSymbol SearchCancellation

Digit SpanLetter-Number

SequencingArithmetic

VCIVCIVCI PRIPRIPRI WMIWMIWMI PSIPSIPSI

Subtests in Italics are Supplemental


Statistical Versus Clinical Significance

“Although statistically significant differences between scores can occur in many clinical groups, the same differences may also occur frequently in the normally functioning population.”

Matarazzo, 1990

Base rate information provides a basis for estimating the rarity or commonness of the examinee’s obtained difference within the normal adult population.


Statistical Significance ofIndex Score Differences

A statistically significant difference between scores, e.g., between the VCI and the PRI, refers to the likelihood that obtaining such a difference by chance is very low (e.g., p < .05) if the true difference between the scores is 0 (Matarazzo & Herman, 1985). The level of significance reflects the level of confidence the examiner can have that the difference between the scores, called the difference score, is a true difference.

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Frequency of Index Score Differences

The prevalence or frequency of an observed score difference in the general population is also referred to as the base rate. Often the difference between an individual’s composite scores (e.g., VCI and PRI) is significant in the statistical sense, but is not infrequent.The statistical significance of differences between scores and the rarity of the difference are two different issues and consequently have different implications for test interpretation. (Matarazzo & Herman, 1985; Payne & Jones, 1957; Sattler, 2001; and Silverstein, 1981.)


Frequency of Index Score Differences

Index score discrepancies of the WISC–IV standardization sample vary as a function of ability level, not age. Table B.2 provides the base rate data by overall standardization sample and by ability level.Table B.2 also provides the base rate data by the direction of the difference and is based on findings that show the percentages of the score differences are not identical in both directions (Sattler, 2001). For example, for children whose FSIQ is 79 points or less, 16.7% obtained PRI scores 15 or more points higher than their VCI scores, whereas only 10.2% obtained VCI scores 15 or more points higher than their PRI scores.


Differences Between Subtest Scaled Scores

An evaluation of the variability helps the practitioner identify the strengths and weaknesses of the child’s cognitive functioning. As with differences between the index scores, the interpretation of a particular subtest score as especially high or low should take into account the statistical significance of the observed difference and estimates of population base rates.

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Related Assessmentsin Development


WISC–IV Spanish

To be normed entirely in the U.S.Items adapted from WISC–IVWhere adaptation is impossible,

parallel items have been created.Norms equated to full US population.Available Winter 2004 / 2005


WISC–IV IntegratedWISC–IV as a Process Instrument

Data-based testing-the-limits Multiple-choice versions of WISC–IVverbal subtests and Block DesignSpatial Span – Spatial Working

MemoryElithorn Mazes – executive functionsFrequencies of error types

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For More Information:

If you need product information or have questions, concerns, or suggestions for PsychCorp, please call us at 1-800-872-1726, fax us at 1-800-232-1223, or e-mail us at [email protected] . We welcome any comments or questions you may have.

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