What is the DTLA-5? The Detroit Tests of Learning Abilities explained

The DTLA-5 is the Detroit Tests of Learning Abilities, Fifth Edition, a standardized, individually administered battery of "cognitive abilities," the mental skills involved in reasoning, remembering, and processing information. It is published by PRO-ED, authored by Donald D. Hammill, Ronnie L. McGhee, and David J. Ehrler, carries a 2018 copyright, and covers ages 6 years 0 months through 17 years 11 months. A school psychologist, educational diagnostician, or similarly trained examiner gives its 12 subtests one-on-one and scores them online. The DTLA-5 is not marketed as an IQ test; the publisher describes it as a test of specific cognitive abilities. It does produce a General Cognitive Ability composite on the same mean-100 scale that IQ tests use, so in practice it serves as a general ability measure that sits alongside comprehensive intelligence batteries in a full evaluation. This article explains how the test is built and scored, how its global composite differs from a full-scale IQ, and how its contrast between learned knowledge and reasoning is meant to be used.

The Detroit tests are among the oldest cognitive measures still in print. Alexander Rigney's 2019 review in the Journal of Psychoeducational Assessment traces the series to Baker and Leland's 1935 original, notes that it has been in use for more than three quarters of a century as a broad measure of cognitive abilities, and describes the fifth edition as staying true to the original's purpose while updating the theory and psychometrics.

Earlier editions were called the Detroit Tests of Learning Aptitude. The fifth edition changed one word. According to PRO-ED, the authors substituted "abilities" for "aptitude" in the title, citing Anne Anastasi's argument that "abilities" has acquired fewer surplus meanings than "intelligence," "aptitude," or "achievement," and that it implies the qualities measured can be developed, modified, or learned. The abbreviation stayed the same, which is why searches for the older name still lead to the current product.

PRO-ED lists 12 subtests: Humanities/Social Studies, Science/Mathematics, Word Opposites, Word Associations, Geometric Matrices, Geometric Sequences, Sentence Imitation, Word Span, Design Reproduction, Reversed Letters, Trail Making, and Rapid Naming. The subtests combine into nine "composites," summary scores built from two or more subtests. Six are subdomain composites, each formed from two subtests:

• Acquired Knowledge: Humanities/Social Studies and Science/Mathematics, which sample learned information.

• Verbal Comprehension: Word Opposites and Word Associations, which sample vocabulary and word relationships.

• Nonverbal Problem Solving: Geometric Matrices and Geometric Sequences, which sample reasoning with figures and patterns.

• Verbal Memory: Sentence Imitation and Word Span, which sample short-term retention of spoken material.

• Nonverbal Memory: Design Reproduction and Reversed Letters, which sample retention of visual material.

• Processing Speed: Trail Making and Rapid Naming, which sample speed on simple mental tasks.

Two larger domain composites sit above the subdomains. Acquired Knowledge, Verbal Comprehension, and Nonverbal Problem Solving contribute to a Reasoning Ability composite, and Verbal Memory, Nonverbal Memory, and Processing Speed contribute to a Processing Ability composite. At the top, all 12 subtests combine into the General Cognitive Ability composite. Examiners can give one or both domains depending on the purpose of the evaluation.

PRO-ED lists the testing time as 40 minutes to 2 hours, depending on how many subtests are given, and the administration as individual. Scoring is online only through the DTLA-5 Online Scoring and Report System, which the publisher says converts raw scores to scaled scores, builds composite indexes, produces percentile ranks and confidence intervals, flags significant "intraindividual differences" (gaps between a student's own scores), and generates a narrative report.

Subtest "scaled scores" have a mean of 10 and a standard deviation of 3. Composite indexes, including General Cognitive Ability, have a mean of 100 and a standard deviation of 15, and the system also reports percentile ranks and age equivalents. Norms are stratified by age and rest on 1,383 students from 30 states and 354 zip codes tested from 2013 through 2015, a sample the publisher describes as representative of the projected 2015 U.S. school-age population on gender, race, ethnicity, household income, parental education, and region.

The publisher reports internal consistency coefficients of .79 to .90 for subtests, .87 to .95 for subdomain composites, and .95 to .98 for the domain and global composites, with test-retest coefficients following the same pattern. The General Cognitive Ability composite is therefore far more dependable than any single subtest. Validity evidence on the product page includes correlations with other cognitive tests, among them the SB-5, WISC-V, and WJ III, along with diagnostic accuracy analyses and confirmatory factor analysis.

PRO-ED sells the DTLA-5 at qualification Level B, which under the publisher's policy covers examiners with a master's degree in psychology, education, or a closely related field plus formal training in clinical assessment, or equivalent professional credentials.

The General Cognitive Ability composite and a full-scale IQ from a battery such as the WISC-V share a scale and a target. Both use a mean of 100 and a standard deviation of 15, and both are intended as estimates of "g," the general factor that runs through performance on all kinds of cognitive tasks. Our guide to what full-scale IQ means explains why a broad composite is the most reliable number a cognitive test produces. The differences lie in what is sampled, who the norm group is, and what the score is used for.

The content sample is different. According to Pearson, the WISC-V derives its Full Scale IQ and five primary index scores from 10 primary subtests, and its core battery takes about 60 minutes. The DTLA-5 builds its global composite from all 12 of its subtests, and two of them, Humanities/Social Studies and Science/Mathematics, deliberately sample acquired academic knowledge, content a Wechsler full-scale score does not directly include. A strong reasoner with a thin educational history may therefore score somewhat differently on the two tests.

The norm groups are different. The DTLA-5 places a student against 1,383 peers tested in 2013 through 2015, while the WISC-V, published in 2014, uses its own sample. Two tests with different norm groups and different items will not return identical scores for the same child, even when both measure g well, and neither score is "the" IQ.

The intended use is different. PRO-ED calls the DTLA-5 a test of specific cognitive abilities, and Rigney's review describes it as one part of a comprehensive assessment for determining eligibility and understanding a student's strengths and weaknesses relative to peers. A comprehensive intelligence battery is usually the anchor of that evaluation; the DTLA-5 more often adds information about memory, processing speed, and learned knowledge, or cross-checks a full-scale IQ obtained elsewhere.

Independent research adds a caution. Richard McNulty and Randy Floyd reanalyzed the DTLA-5 standardization data with hierarchical exploratory factor analysis in a 2021 article in Psychology in the Schools. They found a strong general factor and some group factors, no evidence justifying the split between Reasoning Ability and Processing Ability or the separation of Acquired Knowledge from Verbal Comprehension, and concluded that the test should be interpreted as a measure of psychometric g rather than used to examine individual strengths and weaknesses for most test-takers. In plain terms, the General Cognitive Ability composite is the DTLA-5's most defensible score, and the finer-grained profile should be read with care.

The DTLA-5 keeps a distinction its older name made explicit. "Aptitude" tests were meant to estimate capacity to learn, and "achievement" tests to measure what has already been learned. Inside the DTLA-5, the Acquired Knowledge subdomain leans toward achievement, while Nonverbal Problem Solving and the memory and speed subtests lean toward capacity. The scoring system's intraindividual comparisons let an examiner ask whether a student's learned knowledge is markedly out of line with reasoning and processing scores, and PRO-ED reports that studies of the test's relationship to achievement were part of its validation.

Historically the same logic ran across tests: an examiner compared an ability composite such as General Cognitive Ability with a separate achievement test and looked for a "severe discrepancy" as evidence of a specific learning disability. Federal practice has moved away from requiring that. The IDEA regulations at 34 CFR 300.307 state that state criteria must not require a severe discrepancy between intellectual ability and achievement to identify a specific learning disability, and must permit a process based on the child's response to scientific, research-based intervention. Karla Stuebing and colleagues' 2002 meta-analysis of 46 studies in the American Educational Research Journal found substantial overlap between poor readers who showed an IQ discrepancy and those who did not, and concluded that the evidence gave little support to discrepancy-based classification.

A DTLA-5 knowledge-versus-reasoning gap is therefore a lead for the evaluation team to investigate alongside classroom data, intervention history, and other tests, never a diagnosis on its own. Our article on intellectual disability versus learning disability explains why the two conditions are defined differently and why both require a qualified clinician or multidisciplinary team to identify. The DTLA-5 informs that judgment. It does not make it.

For students aged 6 to 17, the DTLA-5 is a well-established measure with strong composite-level reliability, a nationally stratified norm sample, and a global score that independent analysis agrees is a sound estimate of general ability. Its limitations are those of any single test: every score carries measurement error, its profile-level scores are weaker than its global score, and a trained professional has to integrate the results.

The DTLA-5 does not cover adults and is not sold to the public. Adults who want a norm-referenced estimate of their own reasoning ability have a different option. The Reasoning and Intelligence Online Test, developed by RIOT IQ with psychometrician Dr. Russell T. Warne for adults 18 and older, uses 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 mean-100, standard-deviation-15 scale. It does not replace an individually administered diagnostic evaluation. Adults curious about where their reasoning falls relative to a normed sample can take the RIOT IQ test. Parents whose child has been referred for testing should ask the school psychologist which battery is being used and how its composites will be interpreted.

DTLA-5 stands for Detroit Tests of Learning Abilities, Fifth Edition. Earlier editions were titled Detroit Tests of Learning Aptitude, and the fifth edition changed "aptitude" to "abilities" while keeping the abbreviation.

The publisher describes it as a test of specific cognitive abilities rather than an IQ test, but its General Cognitive Ability composite is a general ability estimate reported on the same mean-100, standard-deviation-15 scale, and independent factor analysis supports reading it as a measure of g. It is used alongside, rather than in place of, comprehensive intelligence batteries in eligibility evaluations.

PRO-ED lists the age range as 6 years 0 months through 17 years 11 months. Norms are stratified by age.

The publisher lists 40 minutes to 2 hours. The full 12-subtest battery takes longest; examiners may administer only the Reasoning Ability or Processing Ability domain when that suits the referral question.

PRO-ED sells it at qualification Level B, which under its policy covers examiners with a master's degree in psychology, education, or a closely related field and formal training in assessment, or equivalent professional credentials. It is individually administered and scored online.

Subtest scaled scores (mean 10, standard deviation 3), nine composite indexes (mean 100, standard deviation 15) including General Cognitive Ability, percentile ranks, age equivalents, confidence intervals, and comparisons between a student's own scores.

1. PRO-ED. (n.d.). DTLA-5: Detroit Tests of Learning Abilities–Fifth Edition, Complete Kit. proedinc.com

2. PRO-ED. (n.d.). Qualifications policy. proedinc.com

3. Rigney, A. M. (2019). Test review: Hammill, D. D., McGhee, R. L., & Ehrler, D. J. (2018). Detroit Tests of Learning Abilities–Fifth Edition. Journal of Psychoeducational Assessment, 37(8), 1043-1047. doi.org

4. McNulty, R. J., & Floyd, R. G. (2021). What does the Detroit Tests of Learning Abilities, Fifth Edition measure? Revelations from a hierarchical exploratory factor analysis. Psychology in the Schools, 58(8), 1474-1489. doi.org

5. Pearson. (n.d.). Wechsler Intelligence Scale for Children, Fifth Edition. pearsonassessments.com

6. U.S. Department of Education. (n.d.). 34 CFR § 300.307 Specific learning disabilities. Individuals with Disabilities Education Act. sites.ed.gov

7. Stuebing, K. K., Fletcher, J. M., LeDoux, J. M., Lyon, G. R., Shaywitz, S. E., & Shaywitz, B. A. (2002). Validity of IQ-discrepancy classifications of reading disabilities: A meta-analysis. American Educational Research Journal, 39(2), 469-518. doi.org

Hero photo: A student's hand writing in an exercise book. Photo by Alex Proimos, via Wikimedia Commons, CC BY 2.0 (cropped).