module 6 Intelligence 2 (Interpretation of WAIS-iv)

Question 1

outline the principles for administering the WAIS-IV subtests

Answer 1

1Subtests should be used if an index was invalid or if searching for clarification of level in specific area. Subtests should NOT just be used arbitrarily.

Question 2

list common errors in WAIS-IV test administration

Answer 2

Common errors include;
Mis-timings
Clerical errors
Failing to seek clarification where required.
Scoring leniency
Incorrect calculations.

Question 3

describe considerations for interpretation of the WAIS-IV

Answer 3

It is recommended to progress in order through the recommended stages for scoring and interpretation;(each level should have a degree of proposing/dismissing/confirming hypothesis/es about a person’s ability, given background information also)
LEVEL ONE;
Interpretation and score of the Full Scale IQ. This is usually written as a percentile ranking comparative to same age and socio-cultural group. It is an indicator of global (overall) intelligence, but is of dubious general accuracy if index scores have great variation. To determine if great variation of indexes is present, (23 points difference =significant)statistical tables are consulted. If there are significant variations of indexes, the indexes are focussed on, as opposed to the Full Scale IQ.
The General Ability Index is an alternate global IQ descriptor but is based only on subtests from the VCI and PRI. This is useful if they may be impairments to WMI and /or PSI. The difference between GSIQ and GAI may help outline levels of impairment under specific situations.
FSIQ average is 90-109.(upper extreme is 130+, well above average is 120-129, high average is 110-119, low average is 80-89, well below average is 70-79, lower extreme is 69 or below.)
LEVEL TWO;
Interpret the Index scores and consider CHC scores. The Indices must not have variation of more than 5 points between their subtest scores however, otherwise they are likely to be invalid. If the indices are considered valid, this is the ideal level at which to reflect upon a person’s strengths and weaknesses.
CHC’s or clusters are groups of subtests. Clusters should only be considered valid or interpreted if their subsets do not vary by more than 5 points.
There are nine CHC clusters;
a) Fluid Reasoning (Matrix Reasoning, & Figure Weights)
b) Visual Processing ( Block Design, & Visual puzzles)
(labelled as Visuospatiatial Index on Wisc-v)
c) Verbal Fluid Reasoning ( Similarities, & Comprehension)
d) Lexical Knowledge (Vocabulary & Similarities)
e) General Information ( Comrehension, & Information)
f) Long-Term Memory ( Vocabulary, & Information)
g) Short-term Memory ( Letter-number Sequencing, & Digit Span)
h) Visual-Motor Speed ( Block Design, Coding, & Symbol Search)
i) Problem Solving Without Visual-Motor Speed ( Matrix Reasoning, Visual Puzzles, Picture Completion, & Figure Weights).
When interpreting scores it is important to bear in mind whether variation is an individual strength/weakness but still within normative parameters and thus unlikely to be problematic, or if the variation as well as being an individual strength/weakness is also outside the normative bounds (in which case esp as a below normal, it may cause difficulties functioning under certain conditions.
LEVEL THREE
Interpretation of subtests (only if required, as index scores are preferred as greater psychometric property, if valid). If there is subtest scatter, consider subtest scores but be cautious interpreting them as each subtest alone lacks psychometric credibility.
LEVEL FOUR
A general consideration of why might scores be high or low? Were there behavioural clues? Did the client repeatedly question?Not motivated? Anxious? etc. Was there an individual style of response which contributed to score? (for this, pay particular attention to the Verbal Comprehension Index subset scores). Possible behavioural issues?
Sometimes performing the tests without a timer, can enable further understanding of where specific difficulties lie.
LEVEL FIVE
Consider intrasubtest variation. Ie Usual pattern is to answer earlier questions in the set correctly, and become incorrect with more difficult questions. But if there is a more sporadic pattern, it may indicate issues of attention, attempts at faking, some brain issue etc etc etc. These patterns however are again, lacking in psychometric property (or potentially associated with many nebulous dx’s).

Question 4

explain the ways in which test bias, socioeconomic status and other environmental factors can impact scores on IQ tests amongst racially and ethnically minoritised populations.

Answer 4

IQ scores are impacted by cultural factors mainly in areas of verbal comprehension, but in others too, in terms of being able to understand the questions and relate to them. Socioeconomic factors tend to impact level of schooling, which in turn, has a large impact on the crystallised intelligences such as vocabulary and mathematics. Ethnic minorities may have less opportunities for education.