The WIAT-4 is the achievement test most often on the same evaluation report as the WISC-V, and the one with the longest list of subtests on the page. Pearson's flyers and its sample report are the source for everything below; the sample report is also the best way to learn to read a real one, so this page walks through it.
Download the WIAT-4 sheet (PDF) (the subtests by domain, the composites, the descriptive categories with percentiles and a report-reading planner; two pages, free).
What it is
| WIAT-4 | |
|---|---|
| Publisher, year | Pearson, 2020 (the WIAT-III was 2009) |
| Ages | 4:0 to 50:11; students from pre-kindergarten to grade 12 |
| Given by | Qualification level B: school psychologists, diagnosticians, special-education and reading specialists with assessment training |
| Format | One-to-one, paper or on Pearson's digital platforms; the essay can be scored automatically by Pearson's engine |
| Time | Varies by grade and by the subtests chosen |
| Norms | Age-based, or grade-based by season (fall, winter, spring) |
| Scores | Standard scores (mean 100, SD 15), percentile ranks, stanines, normal curve equivalents, age and grade equivalents, growth scale values |
The 20 subtests
| Domain | Subtests |
|---|---|
| Oral language | Listening Comprehension; Oral Expression |
| Reading | Word Reading; Pseudoword Decoding; Reading Comprehension; Oral Reading Fluency; Orthographic Fluency (new); Decoding Fluency (new); Phonemic Proficiency (new); Orthographic Choice (new, Q-interactive only) |
| Writing | Alphabet Writing Fluency; Spelling; Sentence Composition; Sentence Writing Fluency (new); Essay Composition |
| Mathematics | Math Problem Solving; Numerical Operations; Math Fluency (addition, subtraction, multiplication) |
What the names mean: Pseudoword Decoding is reading made-up words (pure phonics); Orthographic Fluency is reading irregular words fast (sight-word memory); Decoding Fluency is reading pseudowords fast; Phonemic Proficiency is manipulating sounds in words quickly; Orthographic Choice is picking the correctly spelled word. Those five were added because the processing skills under reading, not just the reading itself, are what an evaluation needs to separate.
The composites
| Group | Composites |
|---|---|
| Core academic | Reading; Written Expression; Mathematics; and the Total Achievement composite across them |
| Processing | Phonological Processing; Orthographic Processing (an extended version on Q-interactive) |
| Supplemental | Basic Reading; Decoding; Reading Fluency; Math Fluency; Oral Language; Writing Fluency |
| Dyslexia Index | A screening score from a short set of subtests, included in every kit; Pearson says under 15 minutes |
The scores and the descriptive categories
Every subtest and composite is reported as a standard score with a mean of 100 and a standard deviation of 15, with a confidence interval (the sample report uses 90 percent), a percentile rank, and a descriptive category. The categories, with the share of children the normal curve places in each:
| Score | Descriptor | About this share of children | Percentile |
|---|---|---|---|
| 130 and above | Extremely High | 2% | 98th and above |
| 120 to 129 | Very High | 7% | 91st to 97th |
| 110 to 119 | High Average | 16% | 75th to 90th |
| 90 to 109 | Average | 50% | 25th to 73rd |
| 80 to 89 | Low Average | 16% | 9th to 23rd |
| 70 to 79 | Very Low | 7% | 2nd to 8th |
| 69 and below | Extremely Low | 2% | 2nd and below |
Pearson's report also prints age and grade equivalents (the age or grade at which the child's raw score is the median) and a growth scale value (GSV), an equal-interval number that tracks the same skill across re-tests; the GSV is what to compare year to year, because standard scores can stay flat while the child learns a year's worth.
Reading a real report: Pearson's sample
Pearson's sample score report is a 6th grader, age 11:8, with grade-based fall norms. The Total Achievement composite is 102, Average, 55th percentile, which on its own says nothing is wrong. The page under it:
| Score | Standard score | Percentile | Category |
|---|---|---|---|
| Word Reading | 71 | 3 | Very Low |
| Pseudoword Decoding | 121 | 92 | Very High |
| Oral Reading Fluency | 53 | 0.1 | Extremely Low |
| Orthographic Fluency | 146 | 99.9 | Extremely High |
| Spelling | 133 | 99 | Extremely High |
| Reading Comprehension | 98 | 45 | Average |
| Numerical Operations | 127 | 96 | Very High |
| Math Problem Solving | 91 | 27 | Average |
| Oral Language composite | 134 | 99 | Extremely High |
The composites average these out (Reading 82, Low Average; Mathematics 110, High Average; Written Expression 110), and the Total hides them entirely. The subtests are the finding: a child who decodes nonsense words and spells at the top of the range but reads real words and connected text at the bottom, with maths calculation far ahead of maths reasoning. That is a profile a psychologist would investigate and a tutor would teach to directly (word reading and reading fluency on known material, then word problems), and it is invisible in the overall score. Read every WIAT-4 report from the subtests up.
How it is used
In a school evaluation under IDEA, the WIAT-4 supplies the achievement side; the WISC-V or another cognitive test supplies the ability side; the psychologist looks at the pattern of strengths and weaknesses across both and at the response to earlier intervention. In a private evaluation the same two tests are usual. The WIAT-4's grade-based norms by season also let a school re-test in spring and compare growth scale values, which is how progress under an IEP is often shown. The two other achievement batteries in the same role are the KTEA-3, Pearson's other one, and Riverside's Woodcock-Johnson.
Download the WIAT-4 sheet (PDF) (the subtests, the composites, the categories and the planner; two pages, free).
Where to get help
A 1-on-1 online class with a tutor who holds a master's degree and teaches the US curriculum from Grade 1 number work to AP Calculus, chemistry and physics, at 7 am before school, after 4 pm and on weekend mornings, US time, for US$10 to $13 an hour: the evaluation report read together in the free 30-minute first class, the subtest or cluster the score is really pointing at found, and the term spent on exactly that skill, with the method written out the way the school marks it. How online tutoring from India to the USA works, or the 1-on-1 online tutoring page.
Sources: Pearson, Wechsler Individual Achievement Test, Fourth Edition, product page (publication 2020; ages 4 to 50 and pre-K to grade 12; qualification level B; completion time varies; score types); Pearson, "Get the 411 on WIAT-4" and "WIAT-4: Identify what they need to achieve even more" flyers (2020): 20 subtests and the five new ones, the composite groups, the Dyslexia Index under 15 minutes, automated essay scoring; Pearson, WIAT-4 sample score report (grade-based norms, 2020): the scores and descriptive categories quoted. The shares and percentiles in the category table are the normal-curve reading of a scale with mean 100 and SD 15. Fetched 9 November 2026.
Questions parents ask
1What is the WIAT-4 test?
2How many subtests are on the WIAT-4?
3What is a good WIAT-4 score?
4What is the WIAT-4 Dyslexia Index?
5Who can give the WIAT-4?
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