IQ on the WISC-IV
By Inderbir Kaur Sandhu, Ph.D
My 15 year old son recently took the WISC IV because he doesn't turn in
his work at school. First they thought he might be ADD, but ruled that
out. Can you tell me what his scores mean and what the IQ is?
WISC-IV Scales Composite Scores 90% confidence:
Verbal Comprehension 124 117-128
Perceptual Reasoning 98 92-105
Working Memory 104 97-110
Processing Speed 85 79-94
Full Scale 106 102-110
WISC-IV Subtests Scaled scores:
Block Design 13
Digit Span 9
Picture Concepts 10
Letter-Number Seq. 13
Matrix Reasoning 6
Symbol Search 8
The WISC-IV scaled scores are calculated using a standardized normative table.
For each of the subtests scaled scores, it would be described as the
following based on the WISC-IV guideline (note that it is not advised to
look at the description per se without the detail breakdown that
includes statistics and significance):
Scaled score from 1-4 is described as exceptional weakness, very
poorly developed, or far below average with a corresponding percentile
rank of 1-2.
Scaled score from 5-7 is described as weakness, poorly developed, or
below average with a corresponding percentile rank of 5-16.
Scaled score from 8-12 is described as average with a corresponding
percentile rank of 25-75.
Scaled score from 13-15 is described as strength, well developed, or
above average with a corresponding percentile rank of 84-95.
Scaled score from 16-19 is described as exceptional strength, very
well developed, or superior with a corresponding percentile rank of
On the whole, he scored in the following range for each of the scales
based on the composite score:
Verbal Comprehension: Superior
Perceptual Reasoning: Average
Working Memory: Average
Processing Speed: Low Average
Full Scale IQ is the corresponding IQ score, which is 106 (considered
average). This means his overall scores are seen as Average, with verbal
scores in the highest range and processing speed in the lowest range.
Hope that helps.