Chapter 7Assessment: Intellectual and Cognitive Measures

INTRODUCTION TO CLINICAL PSYCHOLOGY 2EHUNSLEY & LEE

PREPARED BY DR. CATHY CHOVAZ, KING’S COLLEGE, UWO

Defining Intelligence: Theories of Intelligence Assessing Intelligence

Clinical Context Wechsler Intelligence Scales Administration, Scoring, and Interpretation

Issues A closer look at the WAIS-IV Canadian Normative Data Emotional Intelligence Other Intelligence Scales

Topics:

There have been many different attempts to adequately define intelligence

Wechsler (1939): Intelligence is a person’s global capacity to act purposefully, to think in a rational manner, and to deal effectively with his/her environment.

Intelligence – what is it?

1. Factor Models: Two or more factors thought to be more or less at the same level

2. Hierarchical Models: Different levels of factors with some factors being sub-domains of other factors

3. Information Processing Models: Less on the organization and more on how the brain processes information

Theories of Intelligence

1. Charles Spearman: Proposed that all intellectual activities share a common core: General factor, g

• Postulated there were also a number of specific factors, s

• Based on intercorrelations with tests of sensory abilities

• Idea still is retained in most theories of intelligence

2. Thurstone: Primary mental abilities as relatively distinct abilities

• Proposed that the overlap among primary mental abilities was Spearman’s g factor

• Also developed a measure of intelligence based on his model

Theories of Intelligence: Factor Models

1. Raymond Cattell: Believed current tests were too focused on verbal and school-based abilities

• Developed a test based on more perceptual aspects of intelligence

Fluid intelligence: ability to solve problems without drawing on prior experiences (innate intellectual ability)

Crystallized Intelligence: what we have learned from life and our experiences (including formal education)

Theories of Intelligence: Hierarchical Models

1. Sternberg’s Triarchic Theory: Based on how humans process information (three interrelated components)

i. Componential: executive functioning, performance speed, knowledge acquisition

ii.Experiential: the influence of task novelty on problem solving

iii.Contextual: adaptation, alteration, and selection of the environment

Theories of Intelligence: Information Processing Models

2. Gardner’s Theory of Multiple Intelligences:

• Assigned less importance to g• Multiple forms of intelligence ignored in other theories• Educators have designed curriculums based on these

components

Theories of Intelligence: Information Processing Models

Linguistic Interpersonal

Musical Naturalist

Logical- Mathematical Spiritual

Spatial Existential

Bodily - Kinesthetic Moral

Intrapersonal

Read brief case examples in text p. 250 - 251 Intelligence is often assessed in larger

psychological assessments (e.g., memory problems, neuropsychological assessments, head injuries, learning disability evaluations)

Premorbid IQ: intellectual functioning prior to an accident or neurological decline

Important concept for assessment

Assessing Intelligence: Clinical Concepts

Early IQ tests measured ‘mental age (MA)’ (most students at a particular age got a certain number of items on a test correct) relative to the child’s chronological age (CA)

Ratio IQ: MA / CA X 100 7 yr MA / 8 yr CA X 100 = 87.5 2.5 yr MA / 3 yr CA X 100 = 83.3 20 yr MA / 25 yr CA X 100 = 80 Assumes a linear development of learning No longer used

The Wechsler Intelligence Scales

Wechsler developed the Deviation IQ as a solution to problems of Ratio IQ: Mean of 100 and a standard deviation of 15 – based

on the age of the test-taker relative to other test-takers at that age

Wechsler scales use a hierarchical model (with a general IQ and sub-scale specific abilities)

The Wechsler Intelligence Scales

Test norms may not be appropriate for all individuals – e.g., ethnicity, SES, outside the US, disabilities

Test biases may be a part of the test – especially questions specifically drawing on US-related content

Test only focuses on academically related intelligences

The Wechsler Intelligence Scales

Extensive work has been done in Canada regarding establishing standardized norms

Using data derived from testing Canadian normative samples, test developers then developed scaled (standardized scores) from the raw scores

Scaled scores have X=10 and SD = 3 This allows the same statistical procedures as

used with the American data to be applied to the Canadian data

Canadian Normative Data

There are 3 main Wechsler scales:

1. Wechsler Preschool & Primary Scale of Intelligence – 3rd ed. (WPPSI-III): Ages 2 yrs, 6mo. to 7 yrs, 3 mo.

2. Wechsler Intelligence Scale for Children – 4th ed. (WISC-IV): Ages 6-16

3. Wechsler Intelligence Scale for Adults – 4th ed. (WAIS-IV): Ages 16-90

There is also the: Wechsler Abbreviated Scale of Intelligence (WASI-IV):

Shortened version designed for ages 6-89

The Wechsler Intelligence Scales

Previous versions of Wechsler scales used a:1. Verbal IQ (VIQ)2.Performance (non-verbal) IQ (NVIQ)3. Full Scale IQ = PIQ + NVIQ

Current versions use 4 Index or Composite Scores:1. Verbal Comprehension2. Perceptual Reasoning3. Working Memory4. Processing Speed

Wechsler Scales

Extensive training is provided in doctoral programs as well as training sessions for psychologists

Administration and scoring needs to be thoughtful, careful, and meticulous

General interpretive strategy is to move from the general to the specific

Administration, Scoring, and Interpretation Issues

Verbal Comprehension Scale Similarities: Pairs of words (describing

concepts or objects) presented and the subject must explain how the objects are similar

Vocabulary: Defining a series of orally and visually presented words

Information: Questions that address knowledge of events, people, and places

Comprehension: Questions about common concepts and problems and the person must provide the answer or solution

WAIS-IV Content

Perceptual Reasoning Scale Block Design: Colored blocks to create three-

dimensional representations of two-dimensional geometric patterns.

Matrix Reasoning: Incomplete patterns and, from five choices, must select one that completes the pattern

Visual Puzzles: Pieces of a puzzle where images are chosen that go together to match the example

Picture Completion: Pictures of common objects and settings with a missing part

Figure Weights: The person must chose the “weight” depicted in a series of images that would be equivalent to the “weight” depicted in the example

WAIS-IV Content

Working Memory Scale Digit Span: The person is presented with a series of

numbers and must repeat them in the same sequence or in a reversed sequence

Arithmetic: The person solves arithmetic problems and provides the answer orally

Letter-Number Sequencing: Sequences of letters and numbers are presented orally and the person repeats them with the letters in alphabetical order and numbers in ascending order

WAIS-IV Content

Processing Speed Scale Symbol Search: The person must indicate, by

checking a box, whether target symbols occur in the group of symbols presented

Coding: Using a key that matches numbers to symbols, the person must rapidly provide the correct symbols to a list of numbers

Cancellation: The person is presented with a series of different coloured shapes and is asked to cross out images that have a specific shape (e.g., circles) and a specific colour

WAIS-IV Content

Important caveats: Correlation does not mean causation Intelligence is not due to heredity or the

environment but the interplay of the two IQ is not the same as intelligence

Some findings: About 50-60% of IQ is related to genetics Flynn Effect: IQ appears to be increasing over time IQ scores plateau at age 30 IQ declines for some individuals at age 70 IQ is correlated with SES Some small differences in ethnicity found

IQ and its Correlates

From Gardner’s work on Intrapersonal & Interpersonal Intelligence – the ability to understand oneself and others

Several measures of EI including the Emotional Quotient Inventory and the MSCEIT (perceiving, using and managing emotions)

Emotional Intelligence (EI)

EI is positively correlated with: Better social relations for children and adults Better family and intimate relations More positive perception by others Better academic achievement Better psychological well-being

Emotional Intelligence (EI)

Stanford-Binet V: Designed for ages 2-85. Also an IQ mean of 100,

SD of 15. Not as often used outside the US and Canada due to

lack of content adaptations

Kaufman Assessment Battery-II: Focuses on how children and adults learn and

compares to achievement scores

Other Intellectual Functioning Tests

Wechsler Memory Scale III: Focuses on episodic memory (person’s direct

experience to visual and auditory stimuli). Also has X = 100 and SD = 15.

Wechsler Individual Achievement Test (WIAT-II): Focuses on academic and problem solving skills. In conjunction with a Wechsler IQ, assesses for a discrepancy between IQ and achievement and can help diagnose learning disabilities

Other Intellectual Functioning Tests

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