Specific Assessments for Students with Low Vision
One of the most important prerequisites in planning a student's educational program is assessing the student's strengths and weaknesses. Assessment for students with low vision includes comprehensive evaluations by members of the student's multidisciplinary team. Areas of assessment summarized in the following paragraphs include: functional vision assessment, expanded core curriculum assessments, learning media assessments, clinical low vision evaluations, and ophthalmologic and optometric evaluations. These tests are specific to vision related fields. State tests and standards of learning for students' with low vision are not addressed in this fact sheet.
The Code of Federal Regulations (34 CFR), sec. 300.532: Assessment/Low Vision Assessment and Evaluation states that state and local educational agencies shall ensure that, at a minimum, tests and other evaluation materials must be validated and tailored to assess specific areas of educational need for individual students with visual impairments. Students must be assessed in all areas related to the suspected disability.
Individualized Education Plan (IEP)
Children and youth with low vision have unique educational needs. Research documents that these students often require direct instruction by a teacher for students with visual impairments in areas that are not typically addressed for other students. All students who meet the criteria for visual impairment within their state should have a document that addresses their individual needs. This document, called an Individualized Education Plan (IEP), is used to place a child in the most appropriate educational setting. A thorough assessment for students with visual impairments is the key in creating an adequate IEP. And the assessment process is an essential component in developing appropriate goals and objectives for the student. The following are the most common evaluations given to students with visual impairments to guide their program planning.
Expanded Core Curriculum
The core curriculum designates the minimum standards students must meet in order to advance to the next grade level. Examples of core curricular areas are mathematics, reading, and science. Modifications and adaptations are needed to make these curricula accessible to students who are visually impaired. The Expanded Core Curriculum (ECC) covers additional areas of learning not addressed in the core curriculum that must be assessed and taught for students who are visually impaired. These areas include concepts and skills that are often learned incidentally by sighted peers. Areas of the Expanded Core Curriculum include: orientation and mobility, social interaction, recreation and leisure, use of assistive technology, independent living skills, career education, visual efficiency, self-determination, and compensatory academic skills, including communication modes. A teacher for students with visual impairments must assess each area before beginning a student's educational plan. Evaluations in the areas listed above are critical in order to identify and address weaknesses in the student's repertoire. Students with low vision are often able to pass as being competent in areas of the expanded core because their difficulties are less apparent than those students who are blind and have not received any ECC instruction. Teachers for students with visual impairments must not overlook the needs of these students with low vision when assessing areas of the expanded core curriculum.
These nine areas of the Expanded Core Curriculum can be approached differently for students with low vision and students who are blind. For example, in orientation and mobility instruction, a student who is blind would focus on auditory and tactile cues, while the student with low vision would augment these cues with visual information obtained from the environment. The ECC area of visual efficiency for a student with low vision may mean learning how to use optical devices correctly. However, a student with no vision does not benefit from this training. Although areas of the expanded core curriculum can be very different for students with low vision and for students who are blind, assessment and instruction is equally important for both.
Assistive Technology Assessments
Assistive technology, an area of the expanded core curriculum, refers to any product or service that is used to increase, maintain, or improve functional abilities of students with low vision. Technology assessments address a student's need for such equipment as screen readers, screen magnification, scanners, adaptive keyboards, portable notetakers, closed circuit televisions, augmentative communication devices, braille translation software, braille embossers and braille writing equipment. Assessment in these areas is essential to ensure the appropriate match of technology to student's needs.
Functional Vision Assessments
The functional vision assessment includes a variety of evaluations that test the child's use of vision and visual efficiency in daily activities. The assessment, administered over several sessions, determines how the child accesses his/her visual environment, such as how far s/he can sit from the chalkboard or what print size s/he is able to see. A certified teacher of students with visual impairments completes the assessment; contributions from the child's Orientation and Mobility instructor are helpful as well. Parents, caregivers, and the child's teacher(s) are asked to give input about how the child performs in the community and the school setting. From this assessment, a report is generated that addresses multiple issues:
Near and distance acuity: An acuity measurement is taken at near range (usually at a distance of 16 inches) using a near vision acuity chart. This measurement is often recorded in print size. For example, the teacher may record that the child can read 2M print (large print) at 16 inches. Other functional near tasks might also be used in the evaluation (e.g., how the child accesses information on baseball cards, identification of coins, etc.). Distance visual acuity is typically measured at a distance of 10 or 20 feet. A distance vision chart such as the Feinbloom or Snellen is often used. Other functional distance tasks may include the distance at which the child can see print on the whiteboard or imitate hand movements given by the physical education teacher.
Peripheral visual field: Peripheral vision is the ability to see movement or objects outside of the immediate line of vision. Field loss is measured in degrees. For example, if a child has a 20 degree field loss, his/her visual field does not extend through a complete 180 degrees left to right.
Reading level and speeds: An informal reading inventory indicates the grade level at which a child is reading as well as how fast s/he is reading in comparison to her/his peers.
Current print functioning: The functional vision assessment should state the child's primary mode of reading, whether it is regular print, large print, optical devices, or braille.
Examples of both near and distance information: The assessment report should include examples of environmental features such as faces, signs, and travel cues the child can see and at what distance the child can see each feature.
Light sensitivity: Light sensitivity has implications for how the student performs in a variety of illuminated settings. Children with diagnoses such as albinism or achromatopsia are significantly affected by higher levels of illumination and often perform tasks better under less illumination. There are also visual conditions for which additional lighting is necessary. For a majority of visual conditions, glare will adversely affect visual functioning.
Color perception: Color perception is the ability to perceive differences in color. Because many facets of daily life are influenced by color (e.g., traffic lights, crayons, clothing), a child's ability to differentiate colors needs to be known.
Convergence: Convergence is the necessary inward movement of the eyes in order to focus on a near object.
Eye movements: Eye movements of children and youth refer to the ability to track a moving object in vertical, horizontal, oblique, and circular directions. Such eye movements are used when reading, copying work from the whiteboard, playing sports, and driving.
Eye preference: Eye preference is a term used to describe the eye a person prefers to use for accessing his/her visual environment. Although not always, the preferred eye is often the eye with the better acuity.
Muscle balance: Muscle balance is a term used to describe the alignment of the eyes and how they move together. Proper alignment is needed for the eyes to work together. In addition, proper muscle balance is essential for the ability to converge.
Binocular vision: Binocular vision is a person's ability to perceive three-dimensional depth by fusing the images of each eye.
Depth perception: Depth perception is the ability to distinguish an object's solidity and its position in space relative to other objects not in the same plane.
Visual efficiency: Visual efficiency refers to how well a child completes tasks that require a visual skill.
Educational implications: Educational implications are generally statements that address how a child's visual impairment will affect the child's functioning in a school setting.
Recommendations: Recommendations are typically statements that reflect suggestions from the teacher for students with visual impairments about programming and how to make successful adaptations and accommodations.
Learning Media Assessments
One of the first questions asked about a child's learning is what his/her primary reading medium will be. Teachers and parents may be uncertain as to whether a child should learn braille, rely on large print or use regular print for accessing reading material. The purpose of the learning media assessment is to determine the most effective medium for accessing instruction and teaching methods. A certified teacher of students with visual impairments completes this assessment. The learning media assessment covers both general learning media and literacy media. General learning media are instructional materials and instructional methods. Literacy media refers to reading and writing in print and braille.
Clinical Low Vision Evaluations
A clinical low vision evaluation assesses whether or not a child will benefit from optical devices such as monocular telescopes and/or magnifiers. An optometrist or ophthalmologist who specializes in low vision and the prescription of optical devices performs the clinical low vision evaluation. The evaluation centers on how the child uses his/her vision on a daily basis in both the school setting and at home. Measures for visual acuity, visual fields, and color vision are taken. In addition, the clinical low vision specialist will check for refractive errors and the potential for the student to benefit from optical devices. Often devices are prescribed to meet a specific request of the patient. For example, a patient may want to access prices on items in the grocery store; the doctor may then prescribe a pocket magnifier that can be conveniently placed in a purse or pocket. One of the most beneficial results of the low vision evaluation is the link made between medical and functional aspects of vision loss.
Ophthalmologic and Optometric Evaluations
Only doctors can perform ophthalmologic and optometric evaluations. A medical doctor (ophthalmologist) completes the ophthalmologic evaluation and a doctor of optometry (optometrist) completes the optometric evaluation. The main purposes of the ophthalmology exam are to diagnose eye conditions and examine the health of the eye, as well as to give a prognosis of the visual impairment. A typical ophthalmologic exam involves dilating the patient's eyes in order to view the interior of the eye. Acuity and visual field measurements are taken as well as a check for glaucoma. Use of functional vision is not emphasized. The majority of special education programs across the United States require an eye report from an ophthalmologist in order to initiate special education services for a child with a visual impairment. During optometric evaluations, the doctor verifies the need for refractive lenses and prescribes glasses to improve acuity loss to the greatest extent possible. An optometrist is unable to medically diagnose a visual impairment.
Academic (Standard) Testing
Academic testing is primarily the responsibility of the child's classroom teacher. Children with low vision, however, often require modifications or adaptations in order to complete standard testing in their schools. A teacher for students with visual impairments and a general education teacher should collaborate before administering any tests. Needed modifications may include extended time, enlarged copies, and use of manipulatives.
Related Publications from AFB Press
Corn, A. L. & Koenig, A. J. (1996). Foundations of Low Vision: Clinical and Functional Perspectives. New York: AFB Press.
Hazecamp, J. & Huebner, M. (1989). Program Planning and Evaluation for Blind and Visually Impaired Students: National Guidelines for Educational Excellence. New York: AFB Press.
Brown, D., Simmons, V., & Methvin, J. (1991). The Oregon Project for Visually Impaired and Blind Preschool Children. Medford, Oregon: Jackson Education Service District.
Hatlen, P. (1996). The core curriculum for blind and visually impaired students, including those with additional disabilities. Review, 28(1), 25-32.
Johns, J. L. (1997). Basic Reading Inventory: Pre-Primer through grade Twelve & Early Literacy Assessments. Dubuque, Iowa: Kendall/Hunt Publishing Company.
Koenig, A. J. & Holbrook, M. C. (1995). Learning Media Assessment of Students with Visual Impairments: A Resource Guide for Teachers 2nd Edition. Austin, Texas: Texas School for the Blind and Visually Impaired.
Levack, N. (www.tsbvi.edu). Annotated Bibliography of Curricular Materials Related to the Core Curriculum for Children and Youths with Visual Impairments, Including Those with Multiple Disabilities. Austin, Texas: Texas School for the Blind and Visually Impaired.
Levack, N. (1994). Low Vision: A Resource Guide with Adaptations for Students with Visual Impairments. Austin, Texas: Texas School for the Blind and Visually Impaired.
Pogrund, R., Healy, G., Kelley, J., Levack, N., Martin-Curry, S., Martinez, C., Marz, J., Roberson-Smith, B., & Vrba, A. (1995). TAPS: Teaching Age Appropriate Purposeful Skills. An Orientation and Mobility Curriculum for Students with Visual Impairments. Austin, Texas: Texas School for the Blind and Visually Impaired.
Pugh, G. S., & Erin, J. (Eds.). (1999). Blind and Visually Impaired Students: Educational Service Guidelines. Watertown, MA: Perkins School for the Blind.
Sanford, L. & Burnett, R. (1993). Functional Vision and Media Assessment Report for Students who are Pre-Academic or Academic and Visually Impaired in Grades K-12. Hermitage, TN: Consultants for the Visually Impaired.
Sewell, D. (1997). Assessment Kit: Kit of Informal Tools for Academic Students with Visual Impairments. Austin,Texas: Texas School for the Blind and Visually Impaired.
Smith, A. & O'Donnell, M. (1992). Beyond Arms Reach. Philadelphia: Pennsylvania College of Optometry Press.
American Foundation for the Blind: www.afb.org
American Printing House for the Blind: www.aph.org
Assessment Tools Related to the Expanded Core Curriculum: www.obs.org/napa/assessme.htm
Clinical Measurement of Low Vision in Children: www.aoanet.org/cpg-14-lv.html
Texas School for the Blind and Visually Impaired Curriculum and Assessments: www.tsbvi.edu/publications/index.htm