Individual Tests - Outline

Individual Tests - Outline 1. Aptitude, ability, and achievement 2. Alternatives to major tests of abilities 3. Specific individual tests – infants • Brazelton • Gesell • Bayley • Cattell

Individual Tests - Outline 4. Specific individual tests – young children • McCarthy • Kaufman 5. Specific individual tests – special populations • Columbia • Peabody • Leiter • Porteus

Individual Tests - Outline 6. Specific individual tests – learning disabilities • Illinois • Woodcock-Johnson

Ability, Aptitude, & Achievement • Let’s begin by reviewing the distinctions amongst these three related concepts: • Ability – refers to general capacity to do things. • Aptitude – capacity to carry out a specific function. • Achievement – what has been learned.

Alternatives to the major ability tests • Major ability tests (e.g., Wechsler scales, Stanford-Binet) are excellent tests with known psychometric properties. • However, these tests are not appropriate for use with some of the people we might want to give an ability test. • In particular, the major tests require certain kinds of input & output (e.g., vision, speech) that may not be available to some subjects.

Alternative tests of ability • Alternative tests tend to be created for special purposes or populations. This results in: • fewer people using any given test • a smaller resource base for investigating these tests’ psychometric properties. • less knowledge about the reliability and validity of these tests.

Alternative tests of ability • Alternative tests are often useful as a supplement rather than a replacement for major tests.

Specific individual ability tests • Infant Scales • Brazelton Neonatal Assessment Scale • Gesell Developmental Schedules • Bayley Scales of Infant Development II • Cattell Infant Intelligence Scale 2. Tests for Young Children • McCarthy Scales of Children’s Abilities • Kaufman Assessment Battery for Children

Brazelton Neonatal Assessment Scale • Infants 3 days to 4 weeks old • Well-constructed (makes sense conceptually). • Widely used in research, especially with at-risk infants. • Assesses: • Attention and social responsiveness • Muscle tone and physical movement • Control of alertness • Physiological responses to stress • Psychometric issues – e.g., no norms • good inter-rater reliability; poor test-retest reliability • validity: test does not predict later intelligence – in fact, we don’t know what it is measuring • but Majnemer & Mazer (1998) say 1995 version of test is better • Lundquist & Saber (2000) – detected sex differences among healthy neonates

Gesell Developmental Schedules • Children 21 months to 6 years • First published in 1925 • Original observations provided data on developmental norms • Norms for milestones let tester report comparative rate of development for subject • Test score based on presence/absence of age-related behaviors • Developmental Quotient based on test score • Unrepresentative standardization sample • Poorly documented reliability & validity • Vague instructions. • Questionable scoring system • Only predicts IQ in lowest range • Shepard (1992): GDS should not be used for placement. Issues with inter-judge reliability and predictive validity

Bayley Scales of Infant Development II • Infants 1 – 42 months old • 40 years in the making • Assessments based on normative developmental data. • 2 primary scores: mental and motor. • Assumes that later mental functions depend upon motor development • Psychometric properties: • excellent standardization • good split-half reliability • weakest in youngest age ranges • test score does not predict later IQ • widely used in research, especially with at-risk infants

Cattell Infant Intelligence Scale • Based on normative developmental data • Items taken form Gesell & Stanford-Binet • Also some new items • Arranged in an age scale • Standardized on non-representative sample of 274 children • Published in 1939, never updated • Does not predict IQ in normal range • Ricciuti (1994) says it is widely used in research

McCarthy Scales of Children’s Abilities • Children 2.5 – 8.5 years old. • Developed in early 1970s. • Carefully constructed • General Cognitive Index: composed of scores on 15 of the scales (µ = 100,  = 16) • More research support for verbal and perceptual-performance factors • Less research support for quantitative, memory, and motor factors. • Good reliability for GCI • Concurrent validity: good correlations with WPPSI Verbal, Performance, and Full Scale IQs (Karr et al., 1993) • Widely used in research, especially with at-risk children.

Kaufman Assessment Battery for Children • Children 3-18 years old • 18 subtests combined into 5 global scales: • sequential processing • simultaneous processing • learning • planning • knowledge • Grounded in research – but not the most recent research. • Consists mostly of nonverbal items that require child to perform various information-processing tasks.

Kaufman Assessment Battery for Children • mental processing – measures fluid intelligence • Sequential processing (problems solved in a step-by-step fashion – e.g. digit span, typical math problems) • Simultaneous processing (bits of information organized and integrated to solve a problem – e.g., understanding a paragraph; Ravens Progressive Matrices) • achievement – measures crystallized intelligence • vocabulary • reading comprehension • general knowledge • arithmetic knowledge

Kaufman Assessment Battery for Children • Strengths: first 3 items on mental processing subtests can be used to “teach the task.” • internal consistency ~ .80 for subtests, ~ .90 for 5 global test scores. • Mental Processing composite positively correlated with school achievement; ~ .70 with WISC-R full-scale IQ. • some factor analysis studies support distinction between sequential and simultaneous tasks (but Strommer, 1988 doesn’t). • produces smaller average differences between African-Americans and whites • colorful and interesting items; good norms

Kaufman Assessment Battery for Children • Weaknesses: • Theoretical foundation may be crumbling – as new research makes ideas of Luria, Sperry, Neisser, out of date. • Match between tests and theoretical foundation not as clear as we would like. • Kahan & Noyman (2001) – K-ABC does not distinguish between ability and achievement (which questions a major claimed virtue)

Specific individual ability tests 3. Tests for Handicapped & Special Populations • Columbia Mental Maturity Scale III • Peabody Picture Vocabulary Test III • Leiter International Performance Scale R • Porteus Maze Test 4. Tests for Learning Disabilities • Illinois Test of Psycholinguistic Abilities • Woodcock-Johnson III

Columbia Mental Maturity Scale III • Evaluates ability in normal & variously handicapped children 3-12 years old. • Tests general reasoning ability with multiple-choice items. • No verbal response needed • No fine motor control needed • Child indicates which drawing does not belong among 3-5 drawings on a card. • 92 cards in 8 age scales

Columbia Mental Maturity Scale III • Strengths: • Scores relatively independent of reading skill. • Easy to administer and score. • Untimed (reduces pressure on subject). • Good test manual. • Good reliability • Good standardization sample (n= 2600, stratified by sex, race, region, parents occupn.)

Columbia Mental Maturity Scale III • Weaknesses: • Scale is very vulnerable to error – that is, scores can be seriously inflated by guessing. • Carvajal et al. (1993): weak correlations with WPPSI-R for children 3 years 6 months to 7 years 3 months. Do not use CMMS as substitute for WPPSI-R.

Peabody Picture Vocabulary Test III • Originally developed by Dunn & Dunn (1981). • Updated in 1997. • Intended to measure receptive vocabulary, producing a non-verbal estimate of intelligence. • Multiple choice items require no reading ability. • Subject indicates “Yes” or “No” only • Used with ages 2.5 to 90 years.

Peabody Picture Vocabulary Test III • Two forms: IIIA and IIIB. • Each has 204 plates • Each plate presents 4 numbered pictures. • Task: specify which picture best relates to a spoken word • Items arranged in increasing order of difficulty

Peabody Picture Vocabulary Test III • Good reliabilities: .86 to .97 • Validity: • reasonable correlations with WISC-III VIQ: .91 • Ukrainetz & Blomquist (2002): weak, but significant, correlation with NDW, a vocabulary measure • Tends to underestimate Wechsler or Binet IQs for children at higher and lower ends of IQ range • Only evaluates receptive vocabulary.

Leiter International Performance Scale R • Non-verbal alternative to Stanford-Binet for children 2 to 18 years old. • Strictly a performance scale. • Updated in 1997. • Can be used with deaf and language-disabled subjects. • Reasonably good validity • Useful as an aid to diagnosis in disabled children

Porteus Maze Test • Popular, non-verbal performance test. • First published around 1920. • Can be administered without verbal instructions. • Not much recent research on this test. • Issues: • Standardization sample is very old • No manual • Still used with certain groups (e.g., BD).

Tests of Learning Disabilities • School problems may result from a variety of causes: • low IQ • emotional difficulty • SES • Parents’ characteristics (IQ, education) • Some children have difficulty learning in the absence of such factors.

Tests of Learning Disabilities • Learning disability is usually defined as: • A significant difference between IQ and achievement (often a 2  difference, with IQ higher). • Only in the presence of such a difference can learning disability be diagnosed. • So, thrust of most testing is to compare ability (potential) with achievement (actual)

Illinois Test of Psycholinguistic Abilities • Used with children 2 – 10 years old • Based on an information-processing model: • Failure to respond could result from any of: • defective input system • defective processing between input and output • defective output system

Illinois Test of Psycholinguistic Abilities • Separate subtests for these different “stages” • goal is to isolate the stages where problem lie

Illinois Test of Psycholinguistic Abilities • Issues: • manual gives no information about reliability or validity • manual gives little information about norming sample • normed only on middle-class children • criticized for culturally loaded content • Ottem (2002) says test is useful for language-impaired children

Woodcock-Johnson III • Designed as a broad range test for school settings • Based on Cattell – Horn – Carroll stratified model of intelligence • Assesses • g • specific cognitive abilities • scholastic aptitude • oral language • achievement.

Woodcock-Johnson III • Contains both ability and achievement tests that were normed together – allowing evaluation of presence of discrepancies. • Intended to offer precise localization of impaired function, facilitating intervention. • Cognitive abilities – 10 tests • Extended CAT – 10 more tests • Achievement test – 12 tests • Extended Ach test – 10 more tests

Woodcock-Johnson III • Relatively good psychometric properties • standardization sample n > 8800, & sample was representative • split-half reliabilities for 38 of 42 tests – medians ~ .80s to .90s • Construct validity supported by factor analysis • CAT – each test loads on a single factor • Ach Test – factorially complex: more than just g • Good correlations with other major tests

Individual Tests - Outline