The DAS-II still recognizes and defers to the judgment of the expert clinician, and provides the psychometric basis for allowing this kind of flexibility. The psychologist is encouraged to use his or her information about the child in the room to select a battery, subtests, and item sets that are appropriate to the ability of that child.
DAS-II Subtests Chart (PDF - 30kb)
The DAS–II can be used as a psychoeducational tool to obtain an assessment of cognitive abilities. It is also useful as part of a comprehensive educational or neuropsychological assessment to identify cognitive strengths and weaknesses, intellectual giftedness, or intellectual disability. Results are intended to inform treatment planning and placement decisions in clinical and educational settings, and can provide useful clinical information for neuropsychological evaluation and research purposes.
With the DAS-II you can identify learning disabilities and intellectual disability and properly evaluate Spanish-speaking or deaf or hard of hearing children or giftedness.
Tests of cognitive ability are used extensively in school settings to evaluate the specific cognitive deficits that may contribute to low academic achievement and to predict future academic achievement. To facilitate the assessment of learning disabilities, the DAS–II was linked with WIAT–II to provide information on both cognitive abilities and academic achievement in children from ages 6:0-17:11. Used in conjunction, the DAS-II and WIAT–II provide valuable information for both eligibility and educational intervention purposes.
With the new Phonological Processing Rapid Naming subtests, the DAS-II provides diagnostic subtests that measure cognitive abilities implicated in the dual-deficit hypothesis of developmental dyslexia. This is one of the differences that make a difference, in terms of differential treatment response (e.g., you don’t intervene with phonics when speed of lexical access is the sole deficit).
The DAS–II diagnostic subtests can be used in combination with other instruments specialized for the assessment of cognitive deficits underlying particular learning problems. For instance, poor performance on the Phonological Processing and Rapid Naming subtests may signal problems with the development of fundamental reading skills. In such cases, the Early Reading Success Indicator (ERSI) or the Process Assessment of the Learner: Test Battery for Reading and Writing (PAL) may be used with the DAS–II to enhance the clinical utility of each measure.
Pairing the DAS–II with the ERSI or the PAL provides corroborative information on processes and skills predictive of early reading ability, difficulties, or failure, while parsing out effects from other developmental conditions (e.g., attention-deficit/hyperactivity disorder or a central auditory processing disorder). Additionally, the PAL provides means of tracking a child's progress in early intervention and prevention programs. Using DAS–II results in conjunction with the ERSI or PAL allows the examiner to go beyond the traditional use of ability-achievement discrepancies to determine eligibility for services, and helps school districts to more effectively respond to IDEA 2004.
The DAS-II includes measures of working memory and processing speed, two types of deficits that can underlie diminished performance across academic domains. This is another one of the differences that make a difference, in terms of differential treatment response (e.g., WM deficits are treated with WM interventions – teach encoding strategies, instead of drilling academic content for improvements across academic domains).
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The DSM-IV TR and American Association on Intellectual Disabilities have defined diagnosing intellectual disability as significantly low performance on general cognitive ability with limited adaptive behavior ability.
The design structure of the DAS–II facilitates the assessment of children of very low ability. However, the most accurate diagnosis derives from multiple data sources, including assessment of the individual's functioning at home, at school, and in the community. The Adaptive Behavior Assessment System–Second Edition (ABAS–II) may be used with the DAS–II to enhance the clinical utility of both measures. This pairing provides information on cognitive and adaptive functioning, both of which are required for the proper diagnosis of intellectual disability. In addition, assessment of cognitive functioning provides useful information for placement and training decisions.
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Not only was DAS-II standardized using Spanish directions for the administration of the nonverbal subtests—Copying, Matching Letter-Like Forms, Matrices, Pattern Construction, Picture Similarities, Recall of Designs, Recognition of Pictures, Sequential and Quantitative Reasoning, and Speed of Information Processing, it also
- Offers an expert Spanish translation of nonverbal subtest directions (i.e., blind back translation, expert panel review)
- Provides the SNC, which is useful for testing all children who are not proficient in spoken English
- Gives you the means for a number of other subtractive methods that allow for specific hypothesis testing (e.g., Is limited English proficiency diminishing Word Definitions Scores for this 7-year-old? Administer Naming Vocabulary, which has a reduced expressive language component, but still taps word knowledge
Best practice suggests that clinicians be well versed in the professional practice issues and ethical considerations of assessing children whose primary language is other than English. Spanish speakers may share a primary language with dialectical variations. However, these children will likely be diverse in many other respects. Examiners should familiarize themselves with the specific cultural and linguistic conditions of each child's background when administering the DAS–II Spanish subtests and interpreting performance.
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The DAS–II provides the option to evaluate a client with a hearing impairment. Signed standard administration directions are Included on a CD for Copying, Matching Letter-Like Forms, Matrices, Pattern Construction, Picture Similarities, Recall of Designs, Recognition of Pictures, Sequential and Quantitative Reasoning, and Speed of Information Processing.
A child may use one or any combination of aural/oral or visual modes when communicating. Therefore, the communication method used to administer the DAS–II to a given child may differ across different languages and modalities (e.g., between manually signed American Sign Language and spoken English) with gradations, combinations, and systems in between. Items on the DAS–II may be conveyed differently depending upon the signs and sign language(s) used. The DAS-II provides general guidelines and caveats for administration of DAS–II subtests to children who are Deaf or hard of hearing.
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Children ages 5:0-6:11 years can be administered the school-age battery. The DAS-II has better ceilings and the normative score range is wider than the previous edition. Subtest scores now run from 10 to 90 (that is, the mean plus and minus 4 SDs) and composite scores now run from 30 to 170 (that is, the mean plus and minus 4.67 SDs). A Gifted sample is also included in the validity studies.
It is appropriate to use the Special Nonverbal Composite (SNC) for identifying giftedness in children in non-White populations when the verbal scores are lower due to cultural or environmental influences. The DAS-II GCA score is unbiased in predicting achievement scores of African-American and Hispanic children and in some instances, over-predicts their achievement scores.
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Children referred for assessment in clinical and educational settings frequently show indications of complex problems requiring thorough assessment of cognitive, functional, and neuropsychological functioning. These evaluations identify individuals who may have underlying neurobehavioral problems or are employed to provide an in-depth examination of the neurocognitive abilities of children with known neurological insults.
Neuropsychological evaluations are also used for differential diagnosis of neurological and psychiatric disorders. The psychometric properties of the DAS–II subtests allow for each to be interpreted in isolation, making all DAS–II subtests suitable for inclusion in customized, construct-based assessment batteries.
To incorporate information on memory functioning, the DAS–II can be used with the Children's Memory Scale (CMS) or the NEPSY, both of which include a comprehensive measure of learning and memory functioning in children. These pairings enhance the clinical utility of the DAS–II by providing comprehensive information on children's memory function, among other neuropsychological processes and also provides additional means of assessing the neuropsychological status of children with congenital or acquired brain dysfunction, damage, or disease.
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The comprehensive age range of the DAS–II makes it especially useful in longitudinal studies because the need to switch instruments as the children age is significantly reduced. The psychometric properties of the DAS have been maintained in the DAS–II; in some areas the technical characteristics have exceeded that of DAS, allowing for continued confidence in the DAS–II as a viable research instrument.
The DAS–II can be used to examine the performance of children in a particular diagnostic group or to track the effects of intervention on children's cognitive development. For example, researchers can use the DAS–II to determine the effects of traumatic brain injury on cognitive functioning or to examine whether the effectiveness of school-based interventions varies with specific cognitive abilities. The latter use has special implications for research into the changes in cognitive mechanisms that predict differential response to interventions.
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