What is the Test of Semantic Skills? TOSS-P and TOSS-I: NU explained
The Test of Semantic Skills is an individually administered language test of word meaning for ages 4 to 13. It is not an IQ test. Here is how it works.
Dr. Russell T. WarneChief Scientist
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The Test of Semantic Skills is an individually administered language test that measures how well a child understands and uses word meanings, and it is given, scored and interpreted by a speech-language pathologist or a similarly qualified professional. It is not an IQ test. It samples one narrow slice of language, "semantics" (the meaning side of words and sentences), rather than general reasoning ability, and clinicians usually read it next to a cognitive measure rather than in place of one. The test comes in two versions: the Test of Semantic Skills–Primary (TOSS-P) for younger children and the Test of Semantic Skills–Intermediate: Normative Update (TOSS-I: NU) for older ones. Both were originally LinguiSystems titles and are now carried by PRO-ED, whose catalog listings are the basis for the figures below.
What the Test of Semantic Skills actually measures
Semantics is the part of language that deals with meaning: knowing that a "spatula" belongs in a kitchen, that it is used for flipping, and being able to say so out loud. A child can have clear speech and tidy grammar and still hold a thin store of word meanings, which tends to surface later as trouble with reading comprehension.
Both versions are built around picture scenes rather than isolated flashcards. According to the publisher's description of the primary version, it is composed of 20 realistic line illustrations of everyday scenes, organized around six themes: learning and playing, shopping, around the house, working at school, eating, and health and fitness.
Every task appears in two forms. WPS, which also lists the primary version, describes five receptive task types and five matching expressive ones:
• Labels: the child points to an item that the examiner names, then later names an item the examiner points to.
• Categories: the child points to a member of a named category, then names the category that three items belong to.
• Attributes: the child points to an item given one of its attributes, then describes an item by stating an attribute.
• Functions: the child points to an item whose function has been described, then says what an item does or what we do with it.
• Definitions: the child points to an item that has been defined, then defines an item themselves.
That parallel structure is why clinicians reach for this test rather than a single-word vocabulary measure. A child who points accurately but cannot define or describe shows a different profile from one who struggles on both sides, and the layout makes that contrast visible. Our explainer on what vocabulary tests measure covers how receptive and expressive formats differ.
The two versions, and who each one is for
The versions differ in age band, artwork and in how recently they were normed.
• TOSS-P (Test of Semantic Skills–Primary): WPS lists it for ages 4 years 0 months through 8 years 11 months, individually administered, with a testing time of 25 to 30 minutes. It carries a 2002 copyright and, according to that listing, was normed on a sample of 1,510 children.
• TOSS-I: NU (Test of Semantic Skills–Intermediate: Normative Update): PRO-ED lists it for ages 9 years 0 months through 13 years 11 months, individually administered, with a testing time of 30 minutes. Its picture book contains 18 illustrations on themes of school, learning, community, home, leisure activities and the environment, with vocabulary aimed at late-elementary and middle school students. The kit carries a 2019 copyright.
Note the acronyms. The publisher writes TOSS-P and TOSS-I, for Test Of Semantic Skills; the shorthand "TSS" circulates in school reports but is not the publisher's abbreviation, which matters when ordering forms.
How the scores work
The current intermediate version is the one with a fully documented modern score structure. PRO-ED reports that the TOSS-I: NU yields two subtest scores, Receptive Language and Expressive Language, each expressed as a scaled score with a mean of 10 and a "standard deviation" of 3, which is a measure of how spread out scores are in the norm group. Those two combine into a composite called the Semantic Skills Index, reported on a scale with a mean of 100 and a standard deviation of 15.
The publisher reports that the normative sample for the update contained 1,241 students, stratified by age against geographic region, gender, race and ethnicity, and weighted to 2017 U.S. Census demographics. Internal consistency is reported as an average coefficient alpha of .87 for Receptive Language, .89 for Expressive Language and .93 for the composite. PRO-ED also reports diagnostic accuracy analyses in which a Semantic Skills Index cutoff of 90 produced a sensitivity of .86, a specificity of .85, and a receiver operating characteristic area under the curve of .91.
Those are respectable figures for a focused language measure, and they still leave room for error on any single administration. A sensitivity of .86 means roughly one in seven children in the reference clinical group scored above the cutoff, so the confidence interval around a composite should travel with it into every report.
The primary version reports differently. WPS describes a total score plus raw scores, percentiles, standard scores and age equivalents for the five task categories within each half. Age equivalents are worth treating gently, because they exaggerate small raw-score differences at the ends of the scale.
Why a Semantic Skills Index of 100 is not an IQ of 100
The Semantic Skills Index uses the same familiar 100/15 metric as an IQ score, which invites a misreading. The two numbers are not interchangeable. An IQ score from a full-scale battery aggregates reasoning, memory, visual-spatial work and processing speed. The Semantic Skills Index summarizes ten vocabulary-meaning tasks tied to a fixed set of pictures.
The overlap is real but partial. Word knowledge sits inside what psychometricians call crystallized intelligence, the store of learned knowledge and verbal skill that accumulates with schooling and experience, so semantic scores and verbal IQ scores tend to move together. They diverge whenever a child's exposure to English, schooling history or hearing status has shaped vocabulary independently of reasoning.
This is also why the older practice of requiring a gap between language scores and nonverbal IQ has fallen away. The CATALISE consensus panel led by Dorothy Bishop and Margaret Snowling concluded that a child with a language disorder may have a low level of nonverbal ability without that ruling out a diagnosis of developmental language disorder, and described the large-discrepancy interpretation as discredited. A semantic measure answers a language question and a cognitive measure answers a reasoning question. Where a clinician needs a broad survey of language rather than a semantic close-up, a full battery such as the CELF-5 covers more ground.
Diagnosis belongs to a qualified clinician working from multiple sources. The American Speech-Language-Hearing Association's practice portal describes speech-language pathologists as central to the screening, assessment, diagnosis and treatment of spoken language disorders in school-age children, and describes comprehensive assessment as drawing on both formal and informal tools. The association also notes that standardized tests developed in U.S. English are limited for children who speak other languages or other dialects of English, a live caution for any picture-naming measure.
Edition and availability as of 2026
The publishing history affects what you can actually buy. LinguiSystems, the original publisher, no longer operates a website; the domain does not respond. PRO-ED absorbed the catalog and has since migrated its own product pages, so older proedinc.com product links now fail.
In PRO-ED's current catalog, the TOSS-I: NU complete kit is listed in stock at $227.00 and includes the examiner's manual, picture book and 25 examiner record booklets in a storage box, with those components also sold separately.
The primary version is a different story. PRO-ED no longer lists a boxed TOSS-P complete kit. What remains is a TOSS-P virtual bundle containing the examiner's manual and picture book as digital products, listed at $152.00, plus a 20-pack of paper test forms at $55.00. WPS likewise lists only the TOSS-P test form pack. The primary version has not been formally retired, and it has not been renormed either: it is still a 2002 instrument with 2002 norms, sold mainly as a digital manual plus consumables. When norms are more than two decades old, standard scores drift, so any TOSS-P result should be read as an approximate placement rather than a precise standing against today's children.
Where a general cognitive measure fits
A semantic language test tells you about word meanings. It does not tell you how a person reasons through unfamiliar problems, holds information in mind, or works under time pressure. Those questions call for a separate, norm-referenced cognitive measure, and both kinds of information are most useful when read together by someone qualified to weigh them.
For adults who want a properly normed picture of their own reasoning, the Reasoning and Intelligence Online Test is designed for ages 18 and older. It was developed by RIOT IQ with psychometrician Dr. Russell T. Warne and runs 15 subtests across six cognitive indices covering verbal reasoning, fluid reasoning, spatial ability, working memory, processing speed and reaction time. It takes about 52 minutes and reports scores on the same mean-100, standard-deviation-15 scale used by traditional IQ batteries. It measures cognitive performance in adults and does not replace an individually administered diagnostic evaluation conducted by a qualified professional.
Frequently asked questions
Is the Test of Semantic Skills an IQ test?
No. It is a language test of receptive and expressive word meaning, administered individually by a speech-language pathologist or similarly qualified professional. Its composite uses the same 100/15 score scale as an IQ test, yet it samples vocabulary knowledge rather than general reasoning.
What ages does each version cover?
WPS lists the primary version for ages 4 years 0 months through 8 years 11 months. PRO-ED lists the intermediate normative update for ages 9 years 0 months through 13 years 11 months.
How long does the test take?
Publishers list 25 to 30 minutes for the primary version and 30 minutes for the intermediate normative update, in both cases one-to-one with an examiner.
What is the Semantic Skills Index?
It is the composite score of the TOSS-I: NU, combining the Receptive Language and Expressive Language subtests. PRO-ED reports it on a mean-100, standard-deviation-15 scale, with a reported composite alpha of .93.
Is the TOSS-P still sold?
Partly. PRO-ED no longer lists a complete boxed TOSS-P kit. It sells a virtual bundle of the examiner's manual and picture book plus paper test forms, and WPS lists the test form pack. The primary version has never received a normative update, so its norms date to 2002.
Who can buy and administer it?
Purchase is restricted to qualified professionals under the publishers' test-user qualification policies, and administration requires training in standardized procedures. Scoring and interpretation are clinical work, not something a parent completes at home.
References
1. PRO-ED. (2019). TOSS-I: NU: Test of Semantic Skills–Intermediate: Normative Update, Complete Kit. proedinc.com
3. PRO-ED. (2002). TOSS-P Test Forms %2820%29. proedinc.com
4. Western Psychological Services. (2002). %28TOSS-P%29 Test of Semantic Skills Primary. wpspublish.com
5. American Speech-Language-Hearing Association. Spoken language disorders %5BPractice Portal%5D. asha.org
6. Bishop, D. V. M., Snowling, M. J., Thompson, P. A., Greenhalgh, T., %26 the CATALISE-2 consortium. (2017). Phase 2 of CATALISE: A multinational and multidisciplinary Delphi consensus study of problems with language development: Terminology. Journal of Child Psychology and Psychiatry, 58%2810%29, 1068-1080. pmc.ncbi.nlm.nih.gov
Hero image: “An open book is placed in front of a library shelf.jpg” by Shixart1985, licensed CC BY 2.0, via Wikimedia Commons (https://commons.wikimedia.org/wiki/File%3AAn_open_book_is_placed_in_front_of_a_library_shelf.jpg).
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