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Montilla: Understanding and Administration of Wechsler Adult Intelligence Scale and Wechsler Intelligent Scale for Children  First we were introduced to David Wechsler  We learned that he assisted EG Boring, a renowened historian of psychology wherein they evaluated data from one of the first large-scale administrations of a group intelligence test (army alpha test) while the nation prepared for WW1.  He was also assigned their where administering idividual intelligence tests such as the newly published stanford binet intelligence scale was his primary duty  Wechler believed that intelligence is a whole formed by combining several elements or abilities.  He was dissatisfied with the Stanford Binet intelligence test, as the test was the single score that emerged, the emphasis on time tasks and the fact that the test had been designed specifically for children which is why it should be invalid for adults. GENERAL CONSIDERATIONS DISCUSSED  History and development  Psychometric Properties  Assets and Limitations  Used with diverse groups

HISTORY AND DEVELOPMENT  1930S he began studyig a number of standardized tests and seected 11 differet subtest from his initial battery  1939 - WECHSLER-BELLEVUE Intelligence Scale was published, however it had a number of technical deficiencies, especially on the reliablity of the subtests and the size and representatives of the normative sample  1955 - Wechser Adult Intelligence Scale then emerged as the revised version of the WB. It’s was organized into Verbal and Performance scales. Scoring yielded a Verbal IQ, a Performance IQ, and a Full Scale IQ  1981- WAIS-R - shortly after Wechsler’s death in May of that same year.  It also added new norms and updated the materials, revision was based on 1,880 individuals who were generally representative of the 1970 census and categorized into nine different age groups.

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1997 - The WAIS-III, a subsequent revision of the WAIS and the WAIS-R, was released in 1997.

Primary reason for revision was to update the norms Extending age range Modifying items Developing a higher iq ceiling and floor. Some items were added to each subtests that extended the test’s floor in order to make the test more useful for evaluating individuals with extreme intellectual deficits.  developing index/factor scores  creating linkages to other measures of cognitive functioning/ achievement,  extensive testing of reliability and validity Inclusion of three new subtests, which enabled the calculation of four index scores which will be mentioned in the next slide: clinicians are able to do more different test scores, assesspeople with either greater IQ or age, linking scores with the Wechser Memory scales and calculating both IQ and index/factor scores. However with the revisions, the WAIS-R traditional features were maintainted including the six verbal subtests which provided two subindexes. And the five performance subtests which provided two subindexes. Maintaining these clusters of subtests still enabled practitioners to calculate the Full Scale along with the four secondary indices of Verbal and Performance IQs.

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2008 - WAIS - IV is the most recent revision of the evolving Wechsler Intelligence Scales for Adults

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Telepractice guide was also provided by the reporter

Greater attention to floor and ceilings - The floor of an intelligence test is the lowest level of intelligence the test purports to measure. The WAIS-III had a Full Scale IQ floor of 45; the WAIS-IV has a Full Scale IQ floor of 40. The ceiling of an intelligence test is the highest level of intelligence the test purports to measure. The WAIS-III had a Full Scale IQ ceiling of 155; the WAIS-IV has a Full Scale IQ ceiling of 160. Normed linkages: The WAIS-IV was conormed with the WMS-IV and WIAT-II. Norms and patterns of responses have been developed for special groups, including mild cognitive impairment, borderline intellectual functioning, traumatic brain injury, Alzheimer’s disease, attention-deficit/hyperactivity disorder (ADHD), reading disorder, math disorder, autism, asperger’s syndrome, and depression. One of the most obvious changes has been the elimination of the time-honored verbal versus performance IQ. Instead, the WAIS-IV uses the traditional Full Scale IQ along with four index scores (Verbal Comprehension, Working Memory, Perceptual Reasoning, and Processing Speed). The major rationale for the elimination of the Verbal-Performance IQs is that they are not pure measures but typically combine a number of different abilities. For example, the Verbal IQ included measures of verbal abilities as well as working memory. Thus, it was not a unitary measure of an ability.

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In contrast, relying on the four index scores ensures that relatively pure, theoretically sound measures of abilities have been made. This reliance on a Full Scale IQ plus the four indexes paralleled similar development for the WISC-IV (Wechsler, 2003a, 2003b). In addition, the WAIS-IV includes an optional General Ability Index that combines the Verbal Comprehension and Perceptual Reasoning index scores. An upgrade of the WAIS-IV for neuropsychologists and geropsychologists became available in 2009 (WAISIV/WMS-IV Advanced Clinical Solutions, Pearson, 2009a). A further feature of the WAIS-IV has been the deletion, addition, and revision of subtests. There are, however, situations in which a supplemental subtest can be used in place of a core subtest. The latter types of situation arise when, for some reason, for example, a supplemental subtest might be substituted for a core subtest if:

As you can see, WAIS-Iv contains Contains 10 core subtests which comprises the Full Scale (FIQ) and five supplemental subtests.  Longtime users of previous versions of the Wechsler series of adult tests will note the absence of four subtests (Picture Arrangement, Object Assembly, Coding Recall, and Coding Copy-Digit Symbol) and the addition of three new subtests (Visual Puzzles, Figure Weights, and Cancellation).  Visual Puzzles and Figure Weights are both timed subtests scored on the WAIS-IV Perceptual Reasoning Scale. In Visual Puzzles, the assessee’s task is to identify the parts that went into making a stimulus design for example: non-verbal reasoning, abstract reasoning. In Figure Weights, the assessee’s task is to determine what needs to be added to balance a two-sided scale, so this is a test of quantitative and analogical reasoning. In Cancellation, a timed subtest used in calculating the Processing Speed Index, the assessee’s task is to draw lines through targeted pairs of colored shapes (while not drawing lines through nontargeted shapes presented as distractors), ways to test your visual-perceptual speed.  The developers of the WAIS-IV deemed the subtests to be loading on four factors: Verbal Comprehension, Working Memory, Perceptual Reasoning, and Processing Speed.6 (p. 29)  There is also a fifth index score, the General Ability Index (GAI), which is a kind of “composite of two composites.” It is calculated using the similarities, Vocabulary and Information subtests from the Verbal Comprehension Index and the Block Design, Matrix Reasoning and Visual Puzzles subtests from the Perceptual Reasoning Index. The GAI is useful to clinicians as an overall index of intellectual ability.  Two broad scores are also generated, which can be used to summarize general intellectual abilities:  Full Scale IQ (FSIQ), based on the total combined performance of the VCI, PRI, WMI, and PSI  General Ability Index (GAI), based only on the six subtests that comprise the VCI and PRI

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The developers of the WAIS-IV deemed the subtests to be loading on four factors: Verbal Comprehension, Working Memory, Perceptual Reasoning, and Processing Speed.6 (p. 29)  There is also a fifth index score, the General Ability Index (GAI), which is a kind of “composite of two composites.” It is calculated using the similarities, Vocabulary and Information subtests from the Verbal Comprehension Index and the Block Design, Matrix Reasoning and Visual Puzzles subtests from the Perceptual Reasoning Index. The GAI is useful to clinicians as an overall index of intellectual ability. Therefore there are Two broad scores generated, which can be used to summarize general intellectual abilities: General Ability Index (GAI), based only on the six subtests that comprise the VCI and PRI Full Scale IQ (FSIQ), based on the total combined performance of the VCI, Perceptual Reasoning I, WMI, and PSI Another composite score that has clinical application is the Cognitive Proficiency Index (CPI). Comprised of the Working Memory Index and the Processing Speed Index, the CPI is used to identify problems related to working memory or processing speed (Dumont & Willis, 2001). Some researchers have suggested that it can be used in conjunction with the GAI as an aid to better understanding and identifying various learning disabilities (Weiss et al., 2010). Like the GAI and the Full Scale IQ (FSIQ), the CPI was calibrated to have a mean of 100 and a standard deviation of 15. NORMS WERE ALSO UPDATED, more diverse and has greater sensitivity to the needs of older adults

PSYCHOMETRIC PROPERTIES OF WAIS - IV

While these test-retest reliabilities indicate a high degree of temporal stability, there is still some degree of improvement on retesting because of practice effects. Improved performance due to retesting is important to understand; clinicians need to know when to attribute an increase in scores to practice effects and when this might indicate actual clinical improvement.

The WAIS-IV has also been found to produce expected patterns of correlation with a number of additional standard ability measures. One of it is The Delis-Kaplan Executive Functioning System (Delis, Kaplan, & Kramer, 2001) is a series of subtests that measure various aspects of a client’s ability to initiate, plan, and flexibly monitor their behavior. Representative correlations were a .22 between Perceptual Reasoning and the ability to fluidly produce the names of classes of objects (Category Fluency) and a correlation of .77 with Full Scale IQ and the ability to flexibly and rapidly connect combinations of letters and numbers (Trail Making). - This overview of WAIS-IV correlations with various standardized measures provides strong support for WAIS-IV validity.

WECHSLER INTELLIGENT SCALE FOR CHILDREN  1949 - so that children from the age of 5 years 0 months could be assessed in a similar manner.  Easier items, designed for children, were added to the original scales and standardized on 2,200 European American boys and girls selected to be representative of the 1940 census.  However, some evidence shows that Wechsler’s sample may have been overrepresentative of children in the middle and upper socioeconomic levels. Thus, ethnic minorities and children from

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lower socioeconomic levels may have been necessarily penalized when compared with the normative group. 1974 - The WISC-R standardized on a new sample that was more accurately representative of children in the United States.

MAJOR CHANGES  Inclusion of four factor/ index scores (verbal compre, perceptual organization, freedom and distractability,and processing speed)  The new Processing Speed factor involved the inclusion of a new Symbol Search subtest along with the older Coding subtest.  STANDARDIZATION AND RELIABILITY WERE EXCELLENT.  Standardization - The scales were standardized on 2,200 children between the ages of 6 and 16 who closely matched the 1988 census. The sample consisted of 100 boys and 100 girls for each of the different age groups. WISC -IV

New norms closely represeted the U census 

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2004 WISC - IV Integrated  A further potentially useful feature was the publication of the WISC-IV Integrated (Wechsler et al., 2004), which allowed for 12 additional procedures that enabled specialty practitioners the option of analyzing the underlying processes clients go through when making their responses (see McCloskey & Maerlander, 2005). 2014 - The WISC - V came out with further revisions to the test

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PSYCHOMETRIC PROPERTIES OF WISC - IV  This idea is partially supported in that more than half of the subtests on the WISC-V were retained (with similar content) from the WISC-IV. Reliability on the WISC-IV is generally excellent.  Internal consistency reported in the Technical and Interpretive Manual (Wechsler, 2014b) for the Full Scale IQ ranges from .96 to .97 (M = .96).  The mean internal consistencies for the individual index scores range from .88 (for Processing Speed) to . 93 (for Fluid Reasoning).  The mean (across ages) internal consistencies for the 16 subtests range from a low of .81 for Symbol Search to a high of .94 for Figure Weights.  Test-retest reliability (average 26-day interval) for the Full Scale IQ is .92.  The five index test-retest reliabilities range from a low of .75 for Fluid Reasoning to a high of .94 for Verbal Comprehension.  Average test-retest stability for the subtests range from a low of .71 for Picture Concepts to a high of .90 for Vocabulary.  All subtest stability except Picture Concepts and Matrix Reasoning (.78) are .80 or higher.

ASSETS AND LIMITATIONS  Since their initial publication, the Wechsler intelligence scales have been used in numerous research studies and are widely used throughout the world. Thus, they are familiar to both researchers and practitioners and have a long and extensive history of continued evaluation.

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ASSESING DIVERSE GROUPS

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GuIdelins to consider were discussed by the reporter because The central problem does not seem to be the tests themselves, though. Although these tests are far from perfect, they do provide the sort of information they were intended to provide. The main problem seems to be unequal opportunities that are accurately reflected in how various disadvantaged groups perform on intelligence tests. Despite the conclusion that cognitive tests generally measure what they intend to measure, clinicians still need to take extra care to ensure that accurate data and conclusions are developed. When testing individuals from different cultural backgrounds: (ATTACHED BELOW)

ADMINISTRATION  Generally, the manuals for wechsler provide quite clear guidlines in both administiring and scoring.  However, a number of administration and scoring errors on both the trainee and experienced clinicials is far higher than it should be still.  Errors like these can affect the scores dramatically, which will then affect conclusions and recommendations  So the reporter proceede to discuss general guidelines and cautions to do  Before looking into the guidelines, the reporter reviewed on what were the most frequent general errors

Whereas this list covers quite general categories, Moon et al. (1991) have developed a list of the most frequently occurring specific errors along with concrete, specific recommendations to correct for these errors. However, it should be cautioned that these errors may not necessarily be the ones that occur most frequently for the latest versions of the Wechsler intelligence scales (WAIS-IV/WISC-V):

Despite clear guidelines in the manual as well as awareness of frequent errors, examiners are still likely to make mistakes. Thus, optimal training guidelines should be incorporated into graduate programs and continuing education. A recommended format is the Mastery Model, which involves five steps:...