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Visual ImpairmentsSharon Bradley-Johnson and Ruth Ekstrom

ompared with many impairments such as mental retardation andC earning disabilities, visual impairment appears infrequently, withonly 0.4% of students between the ages of 6 and 21 years receivingspecial education services because of a visual impairment ( US . Depart-ment of Education, 1992). The majority of visually impaired individualsare adults; only 9% are younger than 45 years (Vander Kolk, 1981).

In 1879 the federal Act to Promote the Education of the Blind waspassed. Under this act, the American Printing House for the Blind(APH) conducts the Federal Quota Registration annually to determinethe number of students enrolled in schools and agencies so that fundscan be allocated for procuring books and educational materials AFHproduces (Poppe, 1996).As ofJanuary 1995, there were 54,763 studentsregistered. About 15% were in programs for adults, 32% in primarythrough secondary grades, 3% in kindergarten, 11% in preschools, 8%in programs for infants, and 28% were other. The mean age of theadult group was 40 years, consisting of those enrolled in rehabilitationprograms, in programs for people with multiple handicaps, and in res-idential schools. Other registrants usually had handicaps in addition tovisual loss, and many were in nonacademic multihandicapped pro-grams. The majority of students (84%) were enrolled in state depart-ment of education programs, 8% were in residential schools, 5% werein rehabilitation programs, and 3% were in multihandicapped pro-grams. Th e mean age of students in primary through secondary gradestended to be approximately 2 years older than the expected mean age

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of sighted students, ranging &om 8 years 6 months in Grade 1 to 19years 7 months in Grade 12 (Poppe, 1996).

DefinitionsNumerous terms are used to describe the various types of severe visualloss. The terms visually impaired and visually handicapped refer to indi-viduals who require more than corrective lenses to function adequately.Those who are partially sighted as well as those who are blind fall intothese categories.

Individuals who are functionally blind must rely primarily on sensesother than sight to learn. They use auditory (e.g., readers and taperecorders) and tactile means (e.g., braille) to acquire information.

The term legally blind is used in determining eligibility for govern-ment benefits. The term applies to those with central visual acuity of20/200 or less in the better eye with correction or to those with visualacuity of greater than 20/200 but who have a defect of the visual fieldfor which the widest diameter is 20 or less. This classification does notnecessarily mean that an individual is totally blind because more than75% of people classified as legally blind have some usable vision (Amer-ican Foundation for the Blind, n.d.; Vander Kolk, 1981). For planninginstructional programs, this classification is not helpful because manylegally blind individuals can use visual materials. Some organizationsdescribe individuals who mustrely on nonprint materials, such as au-diotapes and braille, as print disabled.

Terms used to describe visually impaired individuals who are notfunctionally blind include low vision, limited vision, and partially sighted.For these individuals, vision is used for learning, but more than correc-tive lenses is needed to d o so. In this chapter, we use the term low vision.These individuals may use regular or large-type material, some may re-quire magnifiers, and some may need auditory and tactile material aswell.

In the educational system, definitions for eligibility for special ed-ucation services because of a visual impairment are based on federalregulations, but they vary somewhat from state to state. According tothe Individuals With Disabilities Education Act (IDEA, 1990), a visualimpairment is one that, even with correction, adversely affects a childseducational performance. The definition for a particular state can be


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obtained from either a state department of education or a local edu-cation agency.

Etiology and Types of Visual ImpairmentThe etiology of severe visual losses may be a result of either congenitalor adventitious factors. Congenital factors involve inheri ted conditions,prenatal damage, or trauma at birth. Examples include congenital cat-aracts, which can be associated with problems such as photophobia ( ie .,abnormal sensitivity to light), strabismus (Le., muscle imbalance thatresults in failure of the eyes to gaze at the same object simultaneously),and nystagmus (i.e., rapid, involuntary movement of the eyeball); reti-nitis pigmentosa, which involves a gradual deterioration of the receptorcells in the eyes that can result in total blindness or a restricted visualfield; anophthalmos, which is the absence of the eyeball; and opticnerve hypoplasia, a condition occurring in utero involving the under-development of the optic nerve.

Adventitious factors causing visual loss involve accidents or diseases.An example is optic atrophy resulting from head trauma or tumors ofthe brain or eye. This condition may result in a loss of the peripheralfield, a decrease in acuity, and photophobia. Corneal disease involvesscarring of the cornea due to injury, allergies, or infections. Diseasessuch as diabetes, hydrocephalus, and multiple sclerosis may also causevisual loss. For a more detailed discussion of types of visual loss, seeHappe and Koenig (1987).

There is considerable heterogeneity in terms of the types of visualloss. Hazekamp and Huebner (1989) noted that there is a continuumof visual impairment ranging from mild losses to functional blindness.Furthermore, a visual loss may be stable, fluctuating, improving, orslowly or rapidly deteriorating. Thus, an individuals instructional needswill be affected by the cause of the condition and the type of loss.

Besides etiology and type of loss, age at onset also affects function-ing and instructional needs. Individuals who lose their vision after theage of 5 usually retain visual memories. These memories can facilitatethe acquisition of certain language concepts, especially concepts thatare difficult to teach to those who have never ha d vision. For example,the concepts of castle, cow, and color are difficult to compre-hend without visual images. Individuals who d o not have a completeunderstanding of these concepts may still use them correctly at times


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because they have learned the concepts by rote. Thus, when assessingindividuals whose visual loss occurred before the age of 5, it is importantto probe questionable responses to determine whether the individualunderstands the concepts adequately. Also, an emphasis on assessmentof vocabulary for young children with a visual loss is advisable so thatmisconceptions or inadequate concept development can be remediatedas soon as possible.

Many visually impaired individuals have other impairments in ad-dition to visual loss. Kirchner (1983) suggested that 30-50% of visuallyimpaired children have one or more additional impairments. Silberman(1981) estimated that more than 60% of visually impaired students haveadditional impairments resulting in delays in gross motor, fine motor,perceptual, language, cognitive, and self-help skills.

Assessment of Visual Impairment: Eye Specialists ReportsTo understand an individuals visual loss, information from the eye spe-cialists report is necessary. This report may include information rele-vant to planning assessment as well as intervention. Hence, this reportshould be considered before administering psychological tests.

There are several types of eye specialists. Ophthalmologists aremedical doctors who diagnose an d treat eye defects an d diseases. Theyalso prescribe medication and lenses as well as perform surgery andother medical treatments. Optometrists are licensed nonmedical spe-cialists who prescribe lenses an d measure refractive errors and muscledisturbances. Opticians grind lenses according to prescriptions and ad-just eyeglass frames, for example.

Ophthalmologists or optometrists reports usually contain infor-mation related to the etiology of vision loss, age at onset, prognosis,required medical interventions and prescriptions, and restrictions onactivities or use of the eyes. Information regarding the etiology of visualloss may help in understanding what, if any, useful vision the individualmay have. For example, as noted previously, the age at onset has impli-cations for concept development. The prognosis can have implicationsfor instruction. If th e prognosis indicates a changing condition, for ex-ample, there may be a need for supportive counseling to help the in-dividual unders tand an d adjust to the changes in vision. If the prognosisis for a gradual deterioration, it may be beneficial to begin braille in-


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struction while the individual still has some useful vision to aid instruc-tion.

Because eye conditions can change rapidly, the report from eyespecialists should be up to date. To be useful, the visual assessmentshould have been completed within the past year.

The following abbreviation information should help in interpret-ing results of eye specialists reports. Visual acuity and field of vision aremeasured separately for each eye. The abbreviation OD stands for oculardexter (Latin for right eye), 0s stands for ocular sinister (Latin forleft eye), and OU stands for oculi unitis or both eyes. Visual acuityrefers to the sharpness of vision. Acuity is measured with and withoutcorrection (lenses) and for both near and distant vision. It is measuredwith a Snellen chart, in which 20/20 indicates normal vision. If acuityis described as 20/200, this means that the individual can see at 20 ftwhat a person with normal vision can see at 200 ft. If the loss is so severethat it cannot be measured with a Snellen chart (greater than 20/400),it may be measured in terms of the ability to count fingers held atvarying distances. This result is abbreviated CF for counts fingers. Ifthe loss is such that the individual cannot count fingers, then acuitymay be measured in terms of ability to see hand movements at varyingdistances. This is abbreviated HM. The abbreviation NLP indicates thatan individual has n o awareness of external light (n o light perception),whereas awareness of light is abbreviated as LP (light perception). Ifacuity is within normal limits, it is abbreviated WNL.

Some individuals may have good central vision but poor peripheralvision. This loss of visual field can occur in one or both eyes. The eyereport will illustrate the degree of loss and where the fields are re-stricted. This information has implications for the most useful directionof gaze. Individuals with a significant loss of visual field must be attentiveto auditory input and learn to move their head and eyes to exploretheir environment.

Assessment of Visual Impairment:Functional Vision AssessmentBecause clinic conditions used by eye specialists are not the same asthose in other settings, recommendations in eye specialists reports mayor may not apply to a classroom or work situation. Thus, a functionalvisual assessment may be carried out to ensure that appropriate envi-


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ronmental accommodations are made. This assessment typically is com-pleted in the classroom or work setting by a teacher of the visuallyimpaired or an orientation and mobility (O&M) specialist. Such assess-ments are not required in all states. Results from a functional visionassessment describe how individuals use their vision. Because of theheterogeneity in the population of visually impaired individuals, twovisually impaired individuals with the same visual acuity may vary greatlyin ability to use their vision. Different visual problems, such as differentvisual fields or the presence or absence of nystagmus or photophobia,is one variable responsible for differences in th e ability to use residualvision. A second factor is individual differences in motivation to usevision (Blind Childrens Center, 1993). Results from a functional visionassessment can provide important information for planning both as-sessments an d interventions. For example, the reports may indicate thetype of lighting needed to optimize the use of vision, the appropriatesize print, the best posture (for those with a limited visual field), theoptimal distance for viewing material, and recommendations for usinglow-vision equipment. An environmental assessment (i.e., the assess-ment of the compatibility of the environment with an individuals ca-pabilities) also may be included (Kelley, Davidson, & Sanspree, 1993).Because of the important implications of this information for the ad-ministration of psychological tests, results from functional vision assess-ments should be sought before beginning a psychological assessment.

Preparing for an AssessmentOrganizing Background InformationA comprehensive, useful psychological assessment of a n individual witha visual impairment requires considerable planning before the admin-istration of tests. Because of the quantity of different types of informa-tion involved, it is usually more timeconsuming to gather, organize, andinterpret background information than it is for sighted individuals.

To assist examiners working in school systems, Bradley-Johnson(1994) provided information organizing checklists for this purpose.One checklist is for use with infants or preschoolers, and another isdesigned for school-age students who are visually impaired .

Besides obta ining information from school an d clinic records andfrom interviews with others who know the individual well, input from


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several specialists is needed to plan a psychological assessment. Clearly,a multidisciplinary effort is critical if test results and recommendationsare to be useful for visually impaired individuals. Because individualswith severe visual losses must rely to a considerable extent on auditoryinpu t, the report from a recent hearing evaluation should be obtainedalong with the eye specialists report. If these reports are no t current,the psychological assessment may need to be postponed until such in-formation is available. The report from a functional vision assessment,if available, also should be reviewed.

If relevant, a report from a qualified O&M specialist also shouldbe obtained. An O&M evaluation can be carried out even for infants.Assessment and intervention for O&M is critical for those with little orno vision to enable them to move about the environment indepen-dently. Examples of skills taught include the use of public transporta-tion; safe travel within the home, school, and work environments; andappropriate walking stride and gait. Information describing oth er hand-icaps or health issues also will require consideration in planning a psy-chological assessment.

Classroom and Workplace ObservationsObserving the individual functioning in a natural environment beforeadministering tests can be highly informative. For examiners with littleor n o experience working with visually impaired individuals, this obser-vation should help prepare them for what to expect during testing.Valuable information can be obtained from this observation for plan-ning realistic and relevant intervention as well. Such observation is par-ticularly important for school-age students. The more systematic theobservational method, however, the more likely the data are to be o bjective. Procedures for systematic direct observation are described byAlessi and Kaye (1983) and Gelfand an d Hartman (1984).

On e aspect of functioning that is especially useful to note whenobserving in the natural environment is the individuals organizationalskills. Individuals who have little usable vision and poor organizationalskills have a difficult time functioning efficiently and independently.Much time is wasted searching for lost items and requesting help fromothers when materials are not well organized and no t returned to theiroriginal location when no longer needed. Unnecessary and frustratingsearches can be avoided if visually impaired individuals are taught or-


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ganizational skills early in life. Teaching organizational habits to youngchildren can begin by having a specific place where toys are stored andrequiring children to return toys to their storage spot when childrenhave finished playing with them. If organization is a problem, this is animportant area to target for intervention.

Test Selection: Areas to ConsiderBecause most tests normed on individuals who are visually impairedare dated, lack technical adequacy, and have little instructional rele-vance, use of additional information sources is important, includingrecords review, interviews, systematic observation, rating scales, and in-dividually or groupadministered tests. Different types of tests should beconsidered, including norm- and criterion-referenced measures andcurriculum-based measurement, to obtain enough data to support con-clusions. Furthermore, a comprehensive assessment is needed to pro-vide a well-integrated picture of an individuals functioning in variousareas of development. It is not wise to base conclusions on assessmentof only on e o r two areas, especially when technically adequate measuresare limited. Areas to consider for assessment include daily living skills,play skills for young children, social skills, intellectual development, be-havior and emotions, vocational skills, language skills, and other areasof achievement.

Adaptive behavior measures that consist of numerous items requir-ing vision will penalize individuals who are visually impaired an d shouldbe avoided when possible. An example of a measure that requires littleif any adjustment for visually impaired school-age students is the Adap-tive Behavior Inventory (L. Brown 8c Leigh, 1986).If a visually impairedindividual uses adaptive devices to complete daily living activities, suchas a braille watch or a slicing guide, the individual should be givencredit on an adaptive behavior scale for performing these skills inde-pendently-

Because of their contribution to all areas of development, play skillsare important to assess for visually impaired infants and preschoolers.For descriptions of tests for this purpose an d special considerations forintervention in this area, see Bradley-Johnson (1994).

Social skills are particularly important to assess for visually impairedpreschoolers through adults: Appropriate social interaction is the log-ical prerequisite to social acceptance (Raver-Lampman, 1990, p. 70).


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Many visually impaired individuals have difficulty in this area becausethey do not have the opportunity to learn some of the social skills thattheir sighted peers learn through observation of others behavior. Ex-amples of difficulties include lack of certain gestures and no t orientingto a speaker. Furthermore, the emotions of individuals with visual im-pairments may be misunderstood because these individuals d o not usethe type of nonverbal communication used by their sighted peers.

Although observation in the natural environment and interviewswith others may provide useful information on social skills, more com-prehensive assessment is often warranted. Students with disabilitieswereincluded in the norm sample for the Social Skills Rating Scale (Gresham& Elliott, 1990), and the items on this rating scale do not penalizestudents with a visual loss. The age range for the scale is from preschoolthrough high school.

Assessment of receptive and expressive language also should beconsidered. Visually impaired preschoolers may be delayed in conceptdevelopment, and individuals without visual memories may not have acomplete understanding of some concepts. Some visually impaired stu-den ts use words in a meaningful way in on e context but not in anothercontext, suggesting an incomplete understanding of the concepts (Hig-gins, 1973). Thus, results from verbal tests should be interpreted cau-tiously, especially for young children. Questionable verbal responsesfrom visually impaired individuals of any age should be probed to en-sure valid results.

When vision is severely impaired, reliance on verbal directions ismore often necessary. Thus, a good understanding of concepts describing position and relationships such as down, over; and Tight is important.Such concepts aid 08cM training and enable m ore ind ependent func-tioning. Some of these concepts are especially difficult to learn for in-dividuals with little or no useful vision and take longer to acquire. Anemphasis on these concepts in assessment, especially with young chil-dren , seems appropriate.

Listening skills are especially useful when vision is limited. Resultsfrom observation of the individual functioning in the natural environ-ment as well as during the assessment should provide useful informationo n the development of listening skills. For individuals with difficultiesin this area, however, an assessment of receptive vocabulary and syntax,attending behavior, hearing, motivation to perform requested tasks, andmemory may be needed to determine which areas require intervention.


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Test Selection: Issues To ConsiderWhen selecting norm-referenced measures, timed tests should be

avoided whenever possible. If an individual reads braille, additional timewill be required because braille reading takes longer than regular-sizeprint. Duckworth and Caton (1986) suggested that braille requiresabout Z1/2 times longer to read than regular print, but this time variesas a function of the readers experience with braille and on the use ofadditional materials such as audiotapes to augment braille text. Readinglarge print takes more time also. In addition, the use of limited visionis tiring. If timed tests are used, a visually impaired individual may bepenalized because of the additional time necessitated by th e visual loss.Also, if frequent breaks are not used during testing, the individual maybecome more fatigued than sighted individuals, resulting in an under-estimate of performance.

To circumvent a visual impairment, if only a portion of a test isused, such as the Verbal section of a Wechsler scale, this restricts therange of skills assessed. Results would be based on a limited sample ofskills and should be interpreted accordingly. Every effort should bemade to use multiple measures for each area tested, especially whenonly portions of tests are given.

Tests in the appropriate medium for the individual being testedwill be needed. If an individuals primary reading medium is braille,then braille materials will be required for testing. Large print or mag-nifiers will be needed by individuals who use primarily large print.Other individuals may need audiotapes or speech synthesizers. Manyindividually administered and g roup administered tests have been tran-scribed into braille an d are available through the APH (P.O. Box 6085,Louisville, KY40206). Large-print and audio materials also are availablethrough the APH.

Th ere are few tests normed o n a visually impaired sample, and fewhave been published within the past 15 years. Although the responserequirements in these tests should be appropriate, the visually impairednorm sample may or may not be an appropriate comparison group.Because of the many factors affecting visual loss and its manifestation,such as age at onset, type of loss, and amount of usable vision, thispopulation is highly heterogeneous. A relatively large norm samplewould be required to ensure adequate representation of the many typesof visual loss. Simeonsson (1986) noted that when tests have somenorms specific to visually impaired individuals, this may involve small,biased samples (eg., students in residential institutions) , or the infor-


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mation may be confounded by individuals with varying amounts of use-ful vision.

Using tests norm ed on a sighted sample also is problematic. If theindividual has the enabling behaviors required to respond to the testitems, and if comparison to sighted peers is desirable, such a test mightbe useful. Using such a measure assumes, however, that the individualhas had experiences similar to those of the sighted sample. This cannotbe the case because of the visual loss. If, for example, the visually im-paired woman had a ttended a residential school and was overprotectedby her parents because of the handicap, then her background wouldbe much different from that of the sighted norm group.

To help address problems with appropriate norm groups, conclu-sions about visually impaired individuals should be based on multiplesources of information, assessment of various areas of development, andperiodic reevaluation. An extensive list of measures, and discussion oftheir technical characteristics, for use with infants through adolescentswas provided in Bradley-Johnson (1994). Tobin (1994) provided similarinformation, along with information on the assessment of blind andvisually impaired adults, based on practices in Great Britain.

The importance of using multiple sources of information whenselecting college students was also addressed in the Rehabilitation Actof 1973. It stated that a college would not be out of compliance inrequiring the submission of test scores even though there is a strongpossibility that these tests do not reflect a handicapped applicants abil-ity. However, . . . the institution must guarantee that admissions deci-sions take into account other factors such as high school grades, rec-ommendations, etc. (p. 22).

Appropriate norm groups are not an issue with criterion-referencedtests. Furthermore, flexible administration procedures and various ma-terials can be used. For braille readers, the APH has tactile supplementsfor both the Revised Brigance Diagnostic Inventory of Early Develop-ment (Brigance, 1991 , covering skills typically learned between birthand 7 years of age, and the Brigance Diagnostic Comprehensive Inven-tory of Basic Skills (Brigance, 1983), covering skills typically taught fromkindergarten to 10th grade. These criterion-referenced tests are exten-sive and cover areas such as daily living, language, play, reading, math-ematics, written language, and general knowledge. Valuable informa-tion for instructional planning can be obtained with these measures.

For monitoring progress in braille reading, a modification of thecurriculum-based measurement procedure described by Shinn (1989)


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was examined by Morgan and Bradley-Johnson (1995). Because brailletakes longer to read than regular print, a 2-min sample (rather than 1min) was used, and 6 s (rather than 3 s) were allowed for er ror correc-tion. Morgan and Bradley-Johnson found that the reliability and validityof this modified procedure for braille readers was highly similar to thatof the original procedure used with sighted individuals. The curriculum-based measurement procedure can be used to monitor individualprogress in braille reading frequently and efficiently and to comparean individuals performance with peers at any grade level.Appropriate Accommodations: Special Equipment and MaterialsTests are standardized to ensure that identical conditions are providedfor everyone taking a particular test. The purpose of standardization isto ensure fair testing of all participants and aid in the interpretation oftest scores. However, the use of many standardized testing conditionsfor individuals with visual impairments is often impossible. To ensurethat tests are fair for these individuals, various comparable testing con-ditions, referred to as accommodations, are used. For visually impairedindividuals, these accommodations could include (a) provision of spe-cial lighting; (b) changes in test scheduling such as allowing extra timeor administering the test over several days; (c ) revision of test directionssuch as reading print directions aloud; (d) revision of test format suchas use of braille, large print, or an audiotape; and (e) revision of re-sponse methods such as dictating answers or using low-vision aids suchas magnification devices, tactile graphs, an abacus, or a computer. A ppropriate accommodations may be described in a functional vision re-port.

Individuals with low vision may read regular o r large-type materials.Some require low-vision equipment. If this is the case, arrangements touse this equipment during testing will be necessary. Examiners shouldbecome familiar with the use of this equipment before an assessment.

There is a wide variety of low-vision equipment, including magni-fiers mounted o n a headband, o n glasses, or on a stand, or some maybe hand held. Book stands are often used to decrease fatigue causedby holding reading materials close to the eyes.

Some individuals with little or n o functional vision use computersystems to scan printed materials to produce braille or speech output.They also may use computers to produce written output. A device sim-ilar to a typewriter, a braille writer, can also be used to produce braille.


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The slowest method for writing braille is to use a hand-held slate andstylus. The slate holds the paper and the stylus is used to press brailledots into the paper.Equipment that enables individuals to respond easily and effi-ciently in the school or work environment should be used during testingas well. Talking calculators, however, may be a n exception. Even thoughthese calculators are used in the school or work environment, theywould invalidate test results on norm-referenced arithmetic or mathe-matics tests. Examples of other equipment that would be appropriatefor use during testing include a braille watch or clock, a braille ruler,an abacus for calculations, and a signature guide (i.e., a metal platewith a space within which individuals write their name). Some individ-uals will need to use bold-line or raised-line paper to make a writtenresponse. According to the Federal Quota Registration for the APH,26% of visually impaired students were visual readers, 10%braille read-ers, 8% auditory readers, 24% prereaders, and 32% nonreaders (i.e.,they lacked a functional reading mode; Poppe, 1996).

During AssessmentFairness in testing includes ensuring that the individuals are comforta-ble in the testing situation and familiar with the setting. Whenever in-dividuals with disabilities are assessed, accessibility of the testing siteshould be considered.

Stress can negatively affect the ability of some visually impairedindividuals to use their residual vision. A tense examiner may miss im-portant observations and nonverbal messages from the examinees.Hence, establishing adequate rapport is important.

To assist examiners in making visually impaired individuals andthemselves cornfortable, Eyde, Nester, Heaton, and Nelson (1994) of-fered the following suggestions:

a. Speak directly to the person. Identify yourself and let the personknow you are speaking to him or her. When you are leaving theperson who is blind, say s o .b. Do not avoid using works like look or see. There are notany reasonable substitutes. Briefly describe the physical layout of theexamining room, especially the furniture arrangement.c. Do not pet or otherwise distract a guide dog without permission.The dog is responsible for the safety of the blind person and is nota pet.


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d. When assisting the person to a chair, simply guide his or her handto the back or arm of the chair for location.e. Do not push or pull the person. Let the person take your armand walk about half a step ahead of him or her. Identify stairs,curbs,or other obstacles as you approach them. (p. 15)The following suggestions also may be useful: (a) Before handing

materials to the person, indicate that you will be doing so and placethe material so that it touches his or her hand; (b) when you are re-cording responses or arranging materials, explain what you are doingso that the person does not wonder what is happening if you are notadministering test items; and (c) be sensitive to fatigue, using severaltesting sessions and frequent breaks.

After Assessment: Interpretation IssuesTo provide a comprehensive picture of an individuals abilities and dif-ficulties, results from testing should be integrated with information ob-tained from interviews, records review, and direct observation. Further-more, the validity of information from norm-referenced tests should beevaluated in light of results obtained from criterion-referenced andcurriculum-based assessment when possible.

Because of the limitations of norm-referenced tests for visually im-paired individuals, conclusions should be based on an integration ofinformation from the assessment of various areas important for devel-opment including social skills, adaptive behavior, play skills for youngchildren, emotions and behavior, intellectual development, vocationalskills for older individuals, language development, and skills in otheracademic areas. Finally, repeated assessment of progress over time is abetter basis for conclusions than a single assessment.

Assessment for Special Education EligibilityTh e mandates of the IDEA (1990) apply to assessment for eligibility forspecial education services. Among other requirements, the IDEA re-quires a multidisciplinary team and use of tests and other evaluationmaterials besides those designed to provide only a general IQ score.With regard to test selection, the IDEA (1990) requires that


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tests are selected and administered so as best to ensure that whena test is administered to a child with impaired sensory, manual, orspeaking skills, the test results accurately reflect the childs aptitudeor achievement level or whatever other factors the test purports tomeasure, rather than reflecting the childs impaired sensory, man-ual, or speaking skills (except where those skills are the factorswhich the test purports to measure). (p.42496)

Monitoring Student ProgressTo enhance accountability in education, the National Assessment of Ed-ucational Progress (NAEP) and many state programs attempt to docu-ment what typical students at various grade levels are able to do. TheIDEA (1990) requires that most students with disabilities be includedin district, state, and national assessments. Despite this requirement,many students with disabilities have been excluded from these testingprograms. In 1994, for example, the NAEP included only 50% of 4th-grade students, 38% of 8th-grade students, and 36% of 12th-grade stu-dents identified as having an individualized education plan (IEP) forspecial education services.

The NAEP has recently implemented new procedures to includemore students with disabilities. Under the old procedure, such studentswere excluded if they were mainstreamed less than 50% of the time inacademic subjects or if the IEP team determined that the student wasincapable of participating meaningfully in the assessment. Under newprocedures, students with an IEP will be included unless the IEP teamdetermines that the student cannot participate or if the students cog-nitive functioning is so severely impaired that he or she cannot partic-ipate even with accommodations (Olson & Goldstein, 1996).

Th e National Center for Educational Outcomes has been pressingfor the inclusion of students with disabilities in national and state ac-countability assessments. They stated that

the ability to extract useful national and state policy-relevant infor-mation on the outcomes of students with disabilities from nationaland state data collection programs is seriously hampered by the ex-tensive exclusion of portions of this population. . . .The categoricalexclusion of students with disabilities perpetuates the myth of in-herent differences. (McGrew, Thurlow, Shriner, & Spiegel, 1992,pp.iii-iv)Siskind (1993b) provided an extensive summary of the types ofmodifications made in 30 statewide criterion-referenced testing pro-


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grams to accommodate students with disabilities. All 30 states providedlarge-print versions of the test and permitted use of visual magnificationdevices; 28 states provided a braille transcription an d perm itted braillewriters. Twenty-three states permitted devices to transform print intotactile form. Electronic readers, such as voice synthesizers, were per-mitted in 19 states, and the same number of states provided answerdocuments with enlarged type. Only 9 states provided audiocassette ver-sions of the test. In a related article, Siskind (1993a) noted that state-wide criterion-referenced tests administered to students who are visuallyimpaired are not always instructionally valid. She urged that attemptsbe made to introduce additional accommodations so that n o student istested in an unfamiliar mode, especially when test results are part ofpromotion o r graduation requirements.

Siskind (1 9 9 3~ ) urveyed 60 South Carolina classroom teachersknowledge of approved modifications for students with disabilities onstate-mandated tests. She concluded that the teachers were not wellinformed on this issue and stated that

if teachers are unaware of the accommodations they can make whentesting children, it is unlikely that allowable accommodations areemployed. Hence, some students are not being tested in the mostappropriate and valid manner, and perhaps more problematic, thereis inequality in the treatment of students with disabilities. (p. 155)Performance assessment is becoming a part of many state assess-

ment programs. In 1994, 38 states were considering o r using some formof performance assessment (Thurlow, 1995). Some issues regarding theinclusion of students with disabilities in performance assessments havebeen described by McLaughlin and Warren (1995):

1. Outcomes-based systems present special educators with a diffi-cult conceptual switch from believing that each student with adisability should have individualized outcomes to accepting thenotion of a common set of outcomes across students.

2. There is still ambiguity among assessment experts regardinghow much accommodation should be provided within an as-sessment program.

3. When one set of scoring standards is defined for all students,with no modifications made for students with disabilities, stu-dents with disabilities may be denied diplomas or otherwise pe-nalized.

4. When results are used for high stakes accountability, the re maybe greater pressure to exempt students with disabilities. Once


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the decision to exempt students with disabilities has been made,there may also be pressure to i d e n q more students as havingdisabilities in order to exempt more students from the assess-ment. (p. 3)

Assessment for Admission to College, Graduate,or Professional SchoolStudents with visual impairments face the same college and graduateschool admissions tests as sighted students. Organizations administeringthese tests provide a variety of accommodations including braille tran-scriptions, large-print versions, and audiotapes. Before testing, studentswho wish to have an accommodation must identlfjr themselves to thetesting organization, request an accommodation, and provide docu-mentation of their disability. Arrangements can then b e made for a ppropriate accommodations. In a few circumstances, testing organiza-tions are unable to provide a requested and preferred accommodation.Voice synthesizers, for example, currently are not commonly available.In such cases, an alternative accommodation must be used for the as-sessment; this may negatively affect the validity of the results.

Bennett, Rock, Kaplan, and Jirele (1988) examined results on theScholastic Aptitude Test (SAT; now known as the Scholastic AssessmentTest) for three groups of visually impaired students: 203 using a brailletranscription, 984 using a large-type version, and 398 using a regular-type version (in some cases with adaptive devices such as magnifiers).All groups were given extra time. Th e mean verbal scores for the threegroups were essentially comparable to those of sighted students. Similarresults were found for students using the large-print and regular-typeversions for the mathematics test, but students using a braille transcription scored lower. Certain mathematical item types were more difficultfor students using the braille transcription. Differential item functiontechniques showed that these students had lower scores than wouldhave been expected on the basis of their total mathematics test scoreon items containing graphics and on items intended to assess relativelynovel content. Bennett et a1 recommended that caution be used intranscribing tests into braille and emphasized the importance of pilottesting braille items.

Braun, Ragosta, and Kaplan (1988) examined the predictive valid-ity of the SAT for 6,255 nondisabled students and 35 visually impaired


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individuals who took a regular edition of the test and 171 individualswho took special versions such as braille transcriptions or large-printversions. The SAT results, combined with high school grade point av-erages, were used to predict standardized freshman-year averages. Cor-relations for visually impaired students who took the regular, and thosewho took the special versions, were both -37. The correlation for non-disabled students was .49. Low but positive residuals indicated that thevisually impaired students performed slightly better than their predictedscores.

The predictive validity of the Graduate Record Examination (GRE)was examined for 105visually impaired individuals using special admin-istration (Braun et al., 1988). The difference between actual first-yearaverage in graduate education an d the first-year average predicted froma combination of GRE results and undergraduate grade point averagewas greater for visually impaired students for whom higher grades werepredicted and less for those for whom lower grades were predicted.Correlations between actual and predicted first-year averages were 2 9for visually impaired students and -63 for nondisabled students.

The construct validity of the GRE for visually impaired studentswas examined by Bennett et al. (1988).They concluded that the three-factor model (verbal, quantitative, and analytical) provided a moder-ately good fit for visually impaired students using regular type and aless adequate fit for visually impaired students taking the large-type,extended-time administrations. The analp cal factor behaved differentlyfor visually impaired students taking the large-type version than for mostother GRE examinees with the item types that compose it. Logical rea-soning and analytical reasoning appeared to fit better as separate fac-tors. In addition, th e analytical scores of these students showed differentrelationships with other factors. There were considerably lower inter-correlations between the verbal and quantitative factors for visually im-paired students who took the large-type version of the test. Bennettet al. emphasized the importance of using these two scores separatelyrather than as part of a composite.

Willingham (1988) examined the college admissions process forstudents with visual disabilities. Compared with other applicants to thesame colleges, visually impaired students were found to be slightly belowaverage with respect to their academic qualifications. The selection pro-cess for visually impaired students and othe r students with disabilitieswas similar to that for other applicants. Overall admissions rates wereslightly but not significantly lower than would be predicted from the


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SAT and high school grade point average. In smaller institutions, how-ever, this difference was significant, suggesting that students with dis-abilities [who] require special equipment o r resources may be less likelyto be admitted in smaller institutions that are perhaps less able to pro-vide those resources (Willingham, 1988, p. 79).

In advising students with visual disabilities who will be taking stan-dardized tests for college or graduate school admission, it is importantthat they (a) learn about the test (e.g., what the test is designed tomeasure, what the test scores mean, and what kinds of testing accom-modations are available); (b ) register early for special administrations,making known their need for accommodations; (c) obtain informationabout the required documentation to support any accommodation theyrequest; and (d) obtain practice materials from the testing companyand use them to familiarize themselves with typical test items.

An important issue in admissions testing is flagging of test scoresto indicate that a test was given under nonstandard conditions. Th epolicy is consistent with the Standards fm Educational and PsychologicalTesting (1985), as suggested by the American Educational Research As-sociation, American Psychological Association, and National Council onMeasurement in Education. Standard 15.4 reads as follows: In schoolsituations involving admissions . . . any modification of standard test ad-ministration procedures or scoring should be described in the testingreports with appropriate cautions regarding the possible effects of suchmodifications on validity (pp. 83-84). In 1979 the Office of CivilRights established an interim policy allowing the flagging of test scoresin college admissions. Although this interim policy remained after thepassage of the Americans With Disabilities Act (ADA) in 1990, there areincreasing concerns about this practice because it may violate portionsof the ADA. According to D. C. Brown (1996), most agree that ad-missions counselors and committees assume the individual has a dis-ability when they see a flagged score (p. 16).A concern is that testingorganizations often flag scores without providing information to assistin interpretation. Those who use test results need to know whether theaccommodation affects the validity of the results. It is important to con-sider, however, that the examinee with a visual impairment or otherdisability probably will use the same accommodation for test taking asthey will in their college or graduate school work. Thus, the test scoreshould reflect how the individual will perform the kinds of tasks r e presented by the test items.

The decision regarding which accommodations to flag varies con-


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290 BUAIKEY-JOHNWN AND EKSIROM

siderably not only between testing organizations but also within orga-nizations and their various testing programs. Students with visual im-pairments may want to inquire about a testing organizations flaggingpolicies when they register for admissions tests to determine which ac-commodations are and are n ot flagged. This information may influencetheir choice of testing accommodations.

Although many with disabilities feel that flagging is a violation ofprivacy, there are circumstances in which flagging can be useful. Thiswould be the case, for example, if an individual with a visual impairmenttook a test using a nonpreferred an d less familiar accommodation. Un-de r such circumstances, the flagging, with an appropriate explanation,might alert the recipient of the test results to the fact that the individualwas placed at a disadvantage because the preferred and usual accom-modation was not available and the result might therefore have beenhigher under the preferred conditions.

Employment TestingThe Guide for Administrating Written Employment Examinations toPersons With Disabilities (Eyde et al., 1994) is the key resource forassessment in this area. This guide contains a summary of legal require-ments, physical accessibility issues, and advance preparation and de-tailed suggestions for testing job applicants who are visually impaired.Suggestions are also presented for interacting with people with disabil-ities.

The ADA requires employers to provide accommodations whentesting individuals with disabilities an d to administer tests in accessiblelocations. The ADA forbids the use of employment tests or other hiringcriteria that screen out individuals with disabilities unless the test orhiring criteria are shown to be job-related for the position under con-sideration. It is also required that tests be selected and administered toapplicants with a disability in such a manner that the results reflect theskills or aptitude of the applicant rather than the impaired sensoryskills, except when such skills are the factors the test purports to mea-sure.

Th e employment examination of visually impaired individuals be-gins with determining whether the applicant qualifies as an individualwith a disability as defined in the Rehabilitation Act of 1973or the ADA.For applicants deemed disabled, the next step is to determine whether


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V i w IMPAIRMENTS91

they can perform the essential job functions, either with or withoutreasonable accommodations as defined by law. This requirement maycall into question the use of tests of general ability for employmentscreening purposes. Employers may be asked to demonstrate thatgeneral-ability instruments are relevant for specific jo b functions. Rea-sonable accommodations include adjusting o r modrfjrlng examinations.Eyde e t al. (1994) stated that testing accommodations should level theplaying field for persons with a disability. Accommodations facilitate apersons capacities, usually through providing a mechanical or otherkind of substitute for the disability (p. 2).

Key considerations when testing individuals with visual impair-ments with written employment examinations are as follows:Provide individual testing to meet the necessary accessibility, pro-

cedural, and time requirements.Provide accessible materials such as braille transcriptions, largeprint, or audiotapes. In some cases the examiner may act as areader. Eyde et al. (1994) provided suggestions about reading atest to a visually impaired examinee.Provide information in advance about permitted aids, such as aslate and stylus, braille writer, or tape recorder for taking notes,computational aids such as an abacus, and low-vision aids.Explain the method to be used to mark answers. Eyde et al.(1994) suggested that when visually impaired individuals use abraille writer to record answers or mark them directly in a large-print test booklet, the answers should then be transferred to aregular answer sheet.Provide appropriate time limits. As previously noted, braille, forexample, takes longer to read than regular print. Eyde et al.(1994) suggested giving nonspeeded (power) tests without anytime limit. They noted that individuals with diabetes (a majorcause of blindness in adults) may experience numbness in thefingers after an hour or so of reading braille and will need eithera break or a change to ano ther test format. They also noted thatspeeded tests are usually omitted for applicants with visual im-pairments.

Performance tests for employment present additional problems.The best solution may be to determine the type of accommodation thejob applicant would require to perform such tasks and administer thetest using that accommodation. The law does not require employers to


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292 BUADLEY-JOIINSON AND EKSIROM

provide accommodations if this would cause the employer unusualhardship.

The assessment of older adults presents special problems becausemany of them have no t learned to use assistive devices, asmany youngerpeople have. Because many older people have experienced hearinglosses that accompany aging, their use of audiotapes also may be limited.Older adults who are hard of hearing or deaf and who lose their visionalso may no longer be able to use their lipreading or sign languageskills. Furthermore, mental health problems in older people that mayaccompany loss of vision, hearing, or both may also require assessment.

ConclusionA multidisciplinary effort is necessary to carry out a valid assessment ofvisually impaired individuals. Reports from other professions (e.g., eyespecialists, O&M specialists) should be reviewed before psychologicaltesting for implications regarding testing procedures. Interviews andobservations in the natural environment are valuable, especially for ex-aminers who are unfamiliar with visual impairment.

Before assessment, the examiner must arrange for, and becomefamiliar with, any special equipment and materials needed for testing.To ensure valid results, special procedures before and during assess-ment have been described. Issues regarding assessment for special ed-ucation, monitoring student progress, college, graduate, o r professionalschool admissions, and work assessment also are noted.

Assessment is changing considerably, including introduction ofcomputer-based testing and the use of alternatives to standardized tests,especially performance tests. Accommodations with the computer cansometimes be better for visually impaired individuals than with paper-and-pencil tests, or they may make appropriate accommodations moredifficult.

Performance tests seem to be less problematic. They often providea more representative work sample than a paper-and-pencil test. How-ever, the tasks used may have to be adapted so that they can be per-formed by individuals with visual disabilities. Such adaptations raisequestions of validity, similar to those posed for paper-and-pencil tests.Research is needed to determine whether performance tests and worksamples have as good or better construct or predictive validity.

Publishers of standardized tests, and organizations offering major


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testing programs, should provide normative and interpretative infor-mation about examinees with visual impairments. Few currently providethis type of assistance. Part of the problem is small samples, in that thepopulation of individuals with visual impairments is not homogeneous.There is wide variation in impairments and a wide range of accommo-dations used by visually impaired examinees. Providing normative in-formation will require the accumulation of data over a period of severalyears, or across similar tests provided by different publishers.A related problem is the need for more consistent criteria fromtest publishers when flagging test scores. Professional organizations suchas the American Psychological Association may have to take the lead inbringing measurement professionals together to consider whether aparticular accommodation may affect the validity of a test and, if so, thekind of information about the score that should be provided to usersof test results. Perhaps flagging should be eliminated in most assess-ments of individuals with visual impairments if the same type of accom-modation is used to answer the test questions that will be used in col-lege, graduate, or professional school examinations.

As Frisby, Reynolds, and Wang (1996) noted, the actual practiceof giving a person a test is in and of itself an equity issue. If equity inassessment is to be provided to individuals with visual impairments,much work is needed.

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