Assessment for Learning Disabilities

This topic is subdivided into two major themes:

• Formal Assessment
• Informal Assessment

Formal assessment of learning disabilities

By formal assessment, I mean using standardized, norm-referenced tests to compare a child's performance to a much larger, normally distributed population of children of the same age. Normative or formal assessment is used to determine eligibility for special education services, identify and pinpoint a specific disability, and assist in educational planning.

Formal assessment is a complex, and multifaceted process. For persons with a specific learning disability, this process involves three specific steps, each directly related to one of the criterions identified in the definitions of a learning disability

Review the IDEA Definition of a Specific Learning Disability

Formal Assessment Procedrues for Learning Disabilities - Substantiation of a Learning Disability

Formal assessment under IDEA also requires that the assessment team gather information under three areas to find a child eligible as having a specific learning disability.

• ability - document that the child has average or above average intelligence.
• processing deficits - document a processing deficit (visual, auditory, processing speed, executive functioning and motor ability). Some professionals have concerns about processing tests. They feel that we should use these with discretion and keep in mind the limitations of these measures as we identify a learning disability.
  • The Uses and Misuses of Processing Tests
• achievement - document that there is a discrepancy between the observed ability and his or her academic performance

David Q Public

At this point, I would like to introduce David Q Public, a hypothetical young boy with a learning disability. David just completed his formal psychoeducational evaluation to determine his continued eligibility for special education services. We will use his psychometric summary to look at assessment processes for children with a learning disability. This is what his summary looks like.

David's Psychometric Profile

Area 1: Average to Above Average Intellectual Functioning

For a child to be identified as having a specific learning disability (LD), the assessment team must document that the child has average to above average intellectual performance. Intelligence is assessed using standardized tests of intellectual functioning. You will remember that for LD, average intellectual peformance would be between an IQ score of 70-115.

As you may remember from the topic on mild mental retardation, the two most commonly used tests are the Stanford-Binet and the Wechsler Intelligence Scales. The psychologist that conducted David's evaluation used the Wechsler Intelligence Scales for Children (WISC).

To review information about the WISC, click on the links below

• Description of the WISC
  • an example of a WISC administration
  • sample items for subtests for verbal abilities
  • sample items for subtests for performance abilities

For a child with a learning disability, you would expect to see a fairly regular pattern of intellectual performance across test scales. When graphed, David's profile fits this pattern.

Note that most of the scores on this assessment are within the average or low average range. His IQ summary shows that his full scale IQ is 89 with a verbal IQ of 91 and a performance IQ of 94. Since these are not significantly discrepant from one another, the full scale IQ is probably the best indicator of his overall intellectual ability and will be the yardstick against which we will compare the other measures.

The effects of the specific learning disability can be seen in the depression of scores on the subtests of arithmetic (an academic subject), coding and picture completion (related to reading abilities). Thus, David's intellectual profile meets the diagnostic requirement for the category of specific learning disability.

Compare this profile with a child who has mild mental retardation:

Area 2: Processing Deficits

The second area of assessment concern is adaptive behavior. Here, a child with mental retardation would need to demonstrate a significantly deficit in two or more areas. Adaptive behaviors can include a variety of skills that help the person meet the standards of personal independence and social competence expected of children (or adults) their age. These skills allow the person to function independently in society.

Processing Deficits

As you can see from Tommy's profile, he meets the requirement for deficits in processing abilities with depressed scores across the Bender Visual-Motor Gestalt Test and the Developmental Test of Visual-Motor Integration showing significant discrepancies with his intellectual scores. For example, the Bender scores (standard scores of 56) indicate that he is functioning significantly below the expected level given his average intellectual performance (IQ 89 - low average). The same is true of his VMI standard score of 60 when compared to his IQ measure of 89. His composite score is well within the range necessary for a diagnosis of specific learning disabilities.

Area 3: Academic Achievement

The last element in the formal assessment process would be measures of academic performance. Since any child with a disability cannot receive special education services without clear evidence that the impairment(s) effect the child's ability to learn, David's psychologist administered the Weschler Individual Achievement Test (WIAT).

Again, you can see that David's profile shows depressed academic performance in basic reading (79), reading comprehension (74), numerical operations (74), spelling (72) and written expression (68). Each of these scores is more than one standard deviation (15 points) below his assessed intellectual ability (89). Also, referring back to the results of David's intellectual assessment, we can see that the pattern of his learning disability is consistent with the results of the WISC where the three subtests related to math operations (coding and arithmetic) and reading (coding and picture arrangement), making him eligible for special education services as a child with a specific learning disability.

Informal Assessment

Informal assessment involves non-standardized, often teacher or therapist made, materials. These tools are used to supplement and extend formal assessment results. The results of informal tests are used to assist the educational team plan instruction and monitor the child's educational progress.

Teachers have many ways to gather informal data

• student records
• student work
• prereferral information
• observation
• interviews

For more information about informal testing techniques and strategies click on the links below

Assessing Children for the Presence of a Disability

(I included this for review. You visited this site in the MIMR topic)

Screening an Adult for a Learning Disability

Go on to What Does an Assessment Mean
or
Go back to Learning Disabilities

E-mail Larry Gallagher at Larry.Gallagher@nau.edu

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