What Is the CAS2 Test? The Cognitive Assessment System and PASS Theory

The CAS2, formally the Cognitive Assessment System, Second Edition, is an individually administered cognitive ability battery for ages 5 through 18, published by PRO-ED in 2014. Written by Jack Naglieri, J. P. Das, and Sam Goldstein, it is built on "PASS theory," which frames cognition as four brain-based processing systems: Planning, Attention, Simultaneous, and Successive processing. The CAS2 is the most prominent attempt to measure children's cognitive ability from a different theoretical blueprint than the traditional IQ battery, which makes it interesting, and makes the debate around it worth understanding.

PASS descends from the functional-systems neuropsychology of A. R. Luria. Instead of asking how smart a child is overall, the CAS2 sets out to measure four processing systems separately: Planning (strategy and self-monitoring), Attention (focus and resistance to distraction), Simultaneous processing (integrating parts into wholes), and Successive processing (handling information in strict order). The battery deliberately avoids vocabulary and acquired-knowledge tasks, which its authors argue makes it fairer for culturally and linguistically diverse children and sharper at isolating processing deficits.

The Core Battery uses eight subtests (two per PASS scale) and the Extended Battery twelve, in roughly 40 to 60 minutes. Subtests range from Planned Codes and Expressive Attention to Matrices, Figure Memory, Word Series, and Visual Digit Span. The Full Scale and four PASS scales are standard scores with a mean of 100 and a standard deviation of 15, normed on 1,342 children and adolescents representative of the U.S. population, with Full Scale reliability reported at .95. A short CAS2: Brief and a teacher-completed CAS2: Rating Scale round out the family.

Functionally, yes: it is a nationally normed, psychologist-administered cognitive battery on the same score scale as the WISC, used for many of the same decisions. Its authors decline the IQ label on theoretical grounds. The mainstream psychometric caution runs the other way: a joint factor analysis by Keith, Kranzler, and Flanagan of the original CAS alongside the Woodcock-Johnson concluded the CAS's scores largely reflect general cognitive ability rather than four cleanly separable processes. A 2020 meta-analysis by Georgiou and colleagues found PASS scores predict academic achievement about as well as full-scale IQs from traditional tests. Read together: the CAS2 measures real cognitive ability well; whether its four-process interpretation adds diagnostic value beyond g remains contested.

• ADHD and executive function evaluations: Low Planning and Attention profiles are pitched as markers that complement behavior ratings; the CAS2 also reports supplemental executive function and working memory composites.

• Learning disability work: Processing-based patterns of strengths and weaknesses are one accepted route in specific learning disability identification.

• Fair assessment: Because content avoids school-taught knowledge, the authors position the CAS2 for children whose language or schooling background could depress scores on traditional batteries; see neuropsychological testing for the broader assessment context.

Ages 5 years 0 months through 18 years 11 months. There is no adult version, unlike the WISC-WAIS pair.

Full Scale and PASS scores average 100 with a standard deviation of 15, so about two-thirds of children score between 85 and 115 on each scale.

Different blueprint: the WISC-V builds index scores around verbal and nonverbal reasoning, working memory, and processing speed, while the CAS2 organizes everything around the four PASS processes and omits acquired-knowledge content.

School and clinical psychologists and similarly qualified examiners; it is a restricted professional instrument, not a test you can take online.

1. Naglieri, J. A., Das, J. P., & Goldstein, S. (2014). Cognitive Assessment System, Second Edition (CAS2). PRO-ED. proedinc.com

2. Naglieri, J. A., & Rojahn, J. (2004). Construct validity of the PASS theory and CAS: Correlations with achievement. Journal of Educational Psychology, 96(1), 174-181. doi.org/10.1037/0022-0663.96.1.174

3. Keith, T. Z., Kranzler, J. H., & Flanagan, D. P. (2001). What does the Cognitive Assessment System (CAS) measure? Joint confirmatory factor analysis of the CAS and the Woodcock-Johnson Tests of Cognitive Ability (3rd edition). School Psychology Review, 30(1), 89-119. doi.org/10.1080/02796015.2001.12086102

4. Georgiou, G. K., Guo, K., Naveenkumar, N., Vieira, A. P. A., & Das, J. P. (2020). PASS theory of intelligence and academic achievement: A meta-analytic review. Intelligence, 79, 101431. doi.org/10.1016/j.intell.2020.101431