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Kaufman Assessment Battery for Children — Second Edition (KABC-II)

The Kaufman Assessment Battery for Children-Second Edition (KABC-II; Kaufman & Kaufman, 2004) is an individually administered measure of the cognitive processing abilities of children and adolescents aged 3 through 18.


The KABC-II is a theory-based clinical instrument that contributes to culturally fair assessment. The KABC-II offers two global summaries: the Fluid-Crystallized Index (FCI), which includes all five scales, and the Mental Processing Index (MPI), which includes the first four scales but not the Knowledge/Crystallized Ability Scale. The test manual states: “Measures of Gc (general cognition) should be excluded from any score that purports to measure a person’s intelligence or overall cognitive ability whenever the measure of Gc is not likely to reflect that person’s level of ability.”

The KABC-II offers a Nonverbal Scale (NVI), which yields a nonverbal index to assess the processing and cognitive abilities of children with whom a nonverbal measure of cognitive ability is appropriate. The Sequential Processing/Short-Term Memory Scale is designed to measure the ability to solve problems by remembering and using an ordered series of images or ideas. The Simultaneous/Visual Processing Scale measures the ability to solve spatial, analogical, or organizational problems that require the processing of many stimuli at one time. The Learning Ability/Long-Term Storage and Retrieval Scale measures the ability to successfully complete different types of learning tasks. Immediate recall and delayed recall tasks are included in this scale. The Planning/Fluid Reasoning Scale measures the ability to solve nonverbal problems that are different from the kinds taught in school. Verbally mediated reasoning must be used to solve the problems. The Knowledge/Crystallized Ability Scale measures knowledge of words and facts using both verbal and pictorial stimuli and requiring either a verbal or pointing response.


Author (yr) Age Range (yrs) Method of Administration/Format Approx. Time to Administer Subscales
Kaufman Assessment Battery for Children – Second Edition (KABC-II) Kaufman & Kaufman (2004) 3–18

Individually administered, norm-referenced measure of cognitive and processing ability; based on Luria’s processing model and the Cattell- Horn-Carroll (CHC) Model; 18 core and supplementary subtests; co-normed with the KTEA-II

Yields scaled scores and percentiles for subtests, standard scores and percentiles for index, and composite scores

30–75 min.

Luria Model: Sequential Index, Simultaneous Index, Planning Index, Learning Index, Knowledge Index, Mental Processing Index, Nonverbal Index

CHC Model: Short Term Memory, Visual Processing, Long-Term Storage and Retrieval, Fluid Reasoning, and Crystallized Ability, Fluid-Crystallized Index

Availability: Pearson Assessment,


Author (yr) Sample Size Topic(s) Addressed Outcome
​Bardikoff & McGonigle-Chalmers (2014)​ 30 (15 high functioning ASD, 15 typical) Nonverbal IQ in ASD

Authors used the nonverbal scale of the KABC-II (NVI) to assess nonverbal components of the WISC-IV (specifically, Perceptual Reasoning Index (PRI) and Processing Speed Index (PSI)).

Results: (1) No significant group differences were found for the PRI subscale of the WISC-IV nor for the NVI subscale of the KABC-II; however, significantly lower scores were obtained for the PRI versus NIV for children with ASD only.

(2) ASD group scored significantly lower than controls on the Processing Speed Index of the WISC-IV. This supports the need to isolate timing criteria when testing IQ in individuals with ASD, which is now the case with the WISC-IV.

Misconceptions regarding cognitive assessment

<p>This table provides information regarding misconceptions surrounding cognitive assessment in general and is not specific to this assessment.</p>
Myth Reality
Full-scale IQ is a good description of a student’s cognitive ability. Students with autism typically demonstrate a profile of scatter on comprehensive cognitive measures, performing better on tasks involving rote skills than on tasks involving problem solving, conceptual thinking, and social knowledge (Mayes & Calhoun, 2008; Meyer, 2001-2002).
If a student has an average IQ, an adaptive behavior measure is unnecessary. Although a student has an average IQ and is even doing well academically, that does not mean that an adaptive measure is not needed. Research indicates many students with autism have deficits in communication, daily living skills,and socialization (Lee& Park, 2007; Myles et al., 2007). Klin and Volkmar (2000) stated that adaptive behavior is a critical area of planning for students with Asperger Syndrome (now referred to as autism spectrum disorder, Level 1) to facilitate transition from the school environment to work and community environments.
If a student demonstrates a well-below-average IQ, the student does not have any cognitive skills. A flat profile of skills may indicate difficulty accessing what the student knows. Formal cognitive assessments may not yield valuable information for assessing current level of functioning and needs for programming. In addition,students with autism spectrum disorder may not be able to generalize skills from the classroom setting to the testing environment, or the manner in which the information is being assessed may prohibit the child from demonstrating mastery of skills. For example, if the student has learned to perform a task in one way with a certain prompt and the assessment asks for it in a different way, the student may not be able to demonstrate knowledge of the skill.
Formal IQ is more valid than informal data from classroom. Informal classroom data provide information about how the student functions on a daily basis. Analyzing forma and informal data to determine patterns of skills and learning is a key component of assessment (Hagiwara, 2001-2002). Informal data from the classroom may be more valuable than information gathered in a contrived one-on- one setting when determining programming for a student with autism spectrum disorder.
If a student has a high IQ or demonstrates high achievement, she should be successful in the general education classroom. Because students with autism spectrum disorder have difficulty with language, communication, and social skills,they may continue to struggle in the general education classroom in activities that involve these skills.