What is the Slosson Intelligence Test?

The Slosson Intelligence Test (SIT) is a brief, individually administered test of verbal intelligence used as a quick "screener," a short measure that flags people who may need fuller cognitive evaluation. Published by Slosson Educational Publications and now in its fourth edition (the SIT-4), it covers ages 4 to 65 and takes about 10 to 20 minutes to give, with all questions asked and answered orally. This article explains what the test measures, where it came from, how its scores work, what screening can and cannot do, and where a full-battery online option fits for adults.

The SIT is one of the oldest brief intelligence screeners still in print. According to the publisher, Slosson Educational Publications of East Aurora, New York, the SIT-4 "provides a quick, reliable index of intellectual ability in children and adults, including those who are visually impaired or blind." Everything is delivered by voice: the examiner reads each question aloud and the examinee answers aloud. There are no puzzles to assemble, no pictures to scan, and no reading required.

That design has practical consequences. The publisher notes the test is verbally administered so it does not penalize examinees who are methodical, fearful, or have reading disabilities, and the SIT-4 adds large color stimulus items so examiners can use it with people who are visually impaired or blind. The trade-off is that the test measures verbal ability almost exclusively, a point covered in the limitations section below.

The SIT sits in the same product niche as other short screeners such as the Kaufman Brief Intelligence Test, which we profile in our guide to the KBIT test. Both trade breadth for speed: they estimate general ability quickly rather than mapping a full cognitive profile.

According to the APA Dictionary of Psychology, Richard L. Slosson developed the original SIT in 1963 as a brief individual test of verbal intelligence for ages 4 and up, consisting of 187 oral questions. The item style closely followed the early Stanford-Binet tradition of orally administered questions arranged by difficulty. Readers who want that backstory can start with our overview of the Stanford-Binet test.

The test was revised in 1991 as the SIT-R and again in 2002 as the SIT-R3, whose complete kit carries the catalog code SIT-R3-1. The current fourth edition, the SIT-4, was prepared by Bradley T. Erford, Sue Larson, and Steven Slosson, and the publisher continues to document the SIT-R3 alongside it. Slosson Educational Publications lists teachers, principals, guidance counselors, special educators, school psychologists, and social workers among the intended users, and distributors classify it as a professional-level instrument that requires relevant training to purchase.

The publisher describes six verbal cognitive domains, with 187 items in total across them.

• General Information (29 items): knowledge of the world and culture, much of it picked up incidentally rather than taught directly.

• Comprehension (33 items): understanding of social behavior and "common sense," including the ability to interpret sayings and proverbs.

• Quantitative (34 items): mental arithmetic, holding numbers in mind and choosing the right operations without paper.

• Similarities and Differences (30 items): explaining what two things or concepts have in common and how they differ.

• Vocabulary (33 items): using, understanding, and defining words orally.

• Auditory Memory (28 items): repeating digit strings forward and backward and recalling sentences.

Notice what is missing. There are no matrix puzzles, block designs, mazes, or timed symbol-coding tasks, so the SIT does not directly sample "fluid reasoning" (solving novel problems), spatial ability, or processing speed the way a full battery does. Distributor materials describe the SIT-4 plainly as a measure of "crystallized" verbal intelligence, the store of knowledge and verbal skill built up through learning.

A screener answers a narrow question: does this person's estimated ability look high enough, or low enough, to justify a longer and more expensive evaluation? Schools have long used the SIT exactly this way, as a first-pass filter in gifted identification and as a quick triage tool when re-evaluating students, with a full battery reserved for those who pass the screen. Our companion article on how gifted testing works walks through where screening sits in that pipeline.

The research record supports the screening role while warning against treating SIT scores as final. In a 1971 study of 724 Massachusetts public school students, Armstrong and colleagues reported a correlation of .92 between the SIT and the Stanford-Binet, with an average absolute difference of about 5.5 IQ points, and concluded the SIT could serve as a valid screening and retesting substitute for the Stanford-Binet. Stewart and Jones reached broadly similar conclusions in their ten-year review of SIT validity research published in Psychology in the Schools.

Later work added cautions. Sattler and Covin found that SIT scores correlated .70 with WISC-R Full Scale IQs among special education students but only .48 among gifted students, and that SIT scores ran about 7 points higher than WISC-R scores in the special education sample, so the two tests' IQs are not interchangeable. Clark and colleagues, studying gifted screening specifically, found only low to moderate agreement among the measures they compared. The practical lesson is the one Dr. Russell T. Warne makes in the video above: shorter tests carry more measurement error, so a brief screener should open doors to further testing, never close them, and no placement decision should rest on a screener alone.

The SIT-R3 yields a "Total Standard Score" with a mean of 100 and a standard deviation, a measure of how spread out scores are, of 16 points, along with percentile ranks, T-scores, normal curve equivalents, and stanines; its norms were based on roughly 2,000 individuals. The publisher lists a standard deviation of 15 as a new feature of the SIT-4, bringing it in line with the scale most modern IQ tests use, and the SIT-4 reports a total standard score plus standard scores for each of the six domains.

The main limitations follow directly from the design.

• Heavy verbal loading: because every item is spoken and answered in words, scores reflect language skill and acquired knowledge as much as reasoning. The publisher's own SIT-R3 materials note the test does not assess nonverbal abilities.

• Not suitable for nonverbal examinees: anyone who cannot readily hear, understand, or speak the language of the test, including deaf examinees, examinees with limited English, and those with expressive language disorders, cannot be fairly assessed with it.

• Screening-level precision: with under 200 brief oral items and 10 to 20 minutes of testing, the SIT cannot match the reliability or diagnostic detail of a full battery, and studies show its scores can drift several points from Wechsler or Stanford-Binet results for the same person.

• Individual administration only: the publisher is explicit that the test cannot be given to groups, so it still requires a trained examiner sitting with one examinee at a time.

The SIT is a tool for professionals screening other people, mostly children in school settings. An adult who wants a serious estimate of their own IQ needs something different: a normed, multi-domain battery rather than a 15-minute verbal screen. That is the gap the RIOT IQ test, the Reasoning and Intelligence Online Test, is built to fill. Developed by RIOT IQ with psychometrician Dr. Russell T. Warne for adults 18 and older, it includes 15 subtests across six cognitive indices (verbal reasoning, fluid reasoning, spatial ability, working memory, processing speed, and reaction time), takes about 52 minutes, and reports scores on the familiar mean-100, standard-deviation-15 scale. Because it samples nonverbal domains alongside verbal ones, it avoids the single-channel problem that limits the SIT, though like any online test it does not replace an individually administered diagnostic evaluation when one is needed for clinical or legal purposes. You can take the RIOT IQ test at riotiq.com.

It is a brief verbal screener professionals use to estimate general cognitive ability quickly, flag children for gifted-program evaluation, and triage re-evaluations before committing to a full battery.

The publisher lists ages 4 through 65 for the current SIT-4 and for the SIT-R3.

About 10 to 20 minutes to administer, according to the publisher, and the SIT-4 is designed so scoring happens during administration.

It is a legitimate, professionally published measure, but it is a screening instrument. Its scores correlate well with full IQ batteries at the group level, yet individual scores can differ by several points from a Wechsler or Stanford-Binet result.

No. The test is entirely oral, so it is inappropriate for examinees who cannot hear, understand, or verbally answer questions in the test's language. It can, however, be used with people who are blind or have reading disabilities.

A Total Standard Score. On the SIT-R3 this has a mean of 100 and a standard deviation of 16; the publisher lists a standard deviation of 15 as a new feature of the SIT-4, along with standard scores for the six verbal domains.

1. Slosson Educational Publications, Inc. (n.d.). Slosson Intelligence Test 4th Edition (SIT-4). slossonplus.com

2. Slosson Educational Publications, Inc. (n.d.). Slosson Intelligence Test-Revised Third Edition (SIT-R3). slossonnews.com

3. American Psychological Association. (n.d.). Slosson Intelligence Test (SIT). In APA Dictionary of Psychology. dictionary.apa.org

4. Armstrong, R. J., et al. (1971). Can scores obtained from the Slosson Intelligence Test be used with as much confidence as scores obtained from the Stanford-Binet Intelligence Scale? ERIC (ED049293). eric.ed.gov

5. Stewart, K. D., %26 Jones, E. C. (1976). Validity of the Slosson Intelligence Test: A ten-year review. Psychology in the Schools, 13(4), 372-380. doi.org

6. Sattler, J. M., %26 Covin, T. M. (1986). Comparison of the Slosson Intelligence Test, revised norms, and WISC-R for children with learning problems and for gifted children. Psychology in the Schools, 23(3), 259-264. doi.org

7. Clark, E., McCallum, R. S., Edwards, R. P., %26 Hildman, L. K. (1987). Use of the Slosson Intelligence Test in screening of gifted children. Journal of School Psychology, 25(2), 189-192. doi.org

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