University of Edinburgh
 

Vision for Doing

Assessing Functional Vision of Learners who are Multiply Disabled

Part 3: Topics Revisited

Appendix III BUST "Staircase Procedure"

When to use the BUST

You will only refer to this Appendix if you have already been successful in carrying out all or most of the sections of the Procedure for assessing vision (the Sections in Chapter 7). Alternatively you may already be certain that there is some measurable visual acuity. For those learners known to be able to see detail of objects and pictures the issue of assessment of vision may centre around how much detail they see.

For full details of the test, and accompanying booklets, the reader should consult the relevant literature -

BUST-LH playing cards - Playful vision testing. Manual and the accompanying Conversion / Comparison Tables for Vision Tests. Both by Eva Lindstedt (1986). Stockholm, Sweden.

Description of BUST

The name BUST is in Swedish short for 'Form Perception Visual Acuity Test'. Designed in Sweden the BUST test of vision gives a measure of the resolving power of the eye. It offers a good approximation to a measure of visual acuity. Its main advantage is in being designed to work with small children and/or people with multiple disability. The material proceeds from simple to slightly more complex tasks during assessment. It can be used for training learners to see detail as well as assessing how much detail is seen. It is also designed to prepare the way for introduction of more conventional tests of sight. Uses have been found in working with learners of a developmentally young age, those with learning difficulties, those with hearing and/or speech impairments, those with multiple disabilities, and for children and adults who come from minority cultures.

The material consists of a set of BUST playing cards; LH playing cards; stickers; a manual with tables for comparing other tests of vision; instructions and a useful booklet.

The 72 BUST playing cards offer pictures of 8 different objects each of which is presented in different sizes. These are used together with larger cards for matching and can be used in conjunction with the real objects which correspond to the pictures (MUG, SPOON, FORK, GLASSES, SCISSORS, FLOWERS, WHEEL, CLOCK). The stickers are offered in addition to the BUST cards. They are intended to be used by learners requiring more time to acquaint themselves with pictures. These enable abstract concepts such as big/small and same/different to be introduced. The LH playing cards require more advanced learning abilities. Some learners may be able to proceed to these following familiarisation with the BUST playing cards and stickers. For those learners who will not be able to advance beyond comprehension of BUST playing cards a useful approximation of visual acuity (ability to see detail) is still offered.

If it is felt that the learner has some understanding of the objects represented (spoon, fork, glasses, etc) then you may be able to proceed directly to the use of the BUST test. Alternatively, you may have decided on the use of this material only after carrying out the rest of the assessment procedure contained in the sections of this book.

Unlike other tests of visual acuity for children there are fewer different pictures crowded on one card. The testing distance is shorter making it easier for the learner to be interested and to understand. The most reliable way of measuring visual acuity is to eventually present the pictures as pairs. The learner must rely on ability to see detail in choosing between a spoon and fork or scissors and spectacles.

The BUST/LH manual gives suggestions on how to carry out the assessment. After much use we developed a slightly quicker way of using the approach. You may, or may not, find this useful. We developed a logical structure to proceed more rapidly through the BUST assessment. For those who would like to use it, this Appendix sets out the process. It is called a 'Staircase Procedure', to give the idea of proceeding in step-wise fashion through the items, not covering every item but quickly homing in on the size of picture which is causing difficulty.

Preparation for Staircase Procedure

  1. Have available a set of BUST/ LH playing cards and objects.
  2. Find out if objects used in the procedure are available in school or other venue. Prepare life-size copies of the pictures. If it is expected that the learner might be able to cope with up to four objects only, then use these. Familiarise the learner with these, and take as long as is needed to do so. There is no need to hurry this test.
  3. Ensure lighting, positioning and seating are optimal for the learner (ask those who know the learner best).
  4. In as much of a social setting as possible, introduce the cards, starting with those familiar to the learner. The size used here is Size 0 - the largest. Use the abilities of the learner - physical, communicational, intellectual - to adjust the methods of presentation. For example, if the learner cannot name, can s/he point, or else can s/he match?
  5. Decide on the learner's response that is to be used - such as a nod, eye blink, pointing movement, or other.
  6. If the learner can handle the pictures, allow him/her to take them and note down the distance from the learner and position taken in doing this.
  7. Use a ruler to measure the distance from the learner's eyes to the picture card.
  8. Make sure that one of the testers is in a good position to observe the learner and record his/her responses. A second person will sit beside (or in front of) the learner to present the cards to him/her.
  9. Once a measure is obtained using both eyes, record for each of the learner's eyes, individually.

The arrangement of the cards is such that:

A = cup

B = scissors

C = glasses

D = spoon

E = fork

F = clock

G = flower

H = wheel

Number the cards (on reverse side) for ease of use. Let:

0 = largest size

9 = smallest size

On the following pages, we have adopted the format where:

(+) = recognises (that is the learner recognises that card (eg; the clock, size number 6)

(-) = does not recognise (that is the learner does not recognises that particular card)

The staircase is built up of different Procedures and Stages. You simply follow the instructions and go to the Procedure and Stage indicated.

Begin with Procedure 1, Stage 1.

Procedure 1

Stage 1

select Number 1 from A to H (one card only) and present this to the learner

(+)
(-)
select No 1 of another A to H
go to Procedure 2
(a familiar picture)

(+)
(-)
select No1 of another A to H (unfamiliar)
go to Procedure 2
(+)
(-)
go to Stage 4
go to Procedure 2

Stage 4

select No 4 from A to H (familiar picture)

(+)
(-)
select No 4 from another A to H (unfamiliar)
go to Stage 2
(+)
(-)
select No 4 from B, C, D or E
go to Stage 2
(+)
(-)
go to Stage 7
go to Stage 3

Stage 7

select No 7 from B, C, D or E

(+)
(-)
select No 7 out of B, C, D, E (not used)
go to Stage 5
(+)
(-)
select No 7 from B, C, D or E (not used)
go to Stage 5
(+)
(-)
go to Stage 9
go to Stage 6

Stage 9

select No 9 from B, C, D or E

(+)
(-)
select No 9 of B, C, D, E (not used)
go to Stage 8
(+)
(-)
select No 9 of B,C,D or E (not used)
go to Stage 8
(+)
(-)
READ OFF TABLE FOR NO 9
READ OFF TABLE FOR NO8
AT APPROPRIATE DISTANCE
AT APPROPRIATE DISTANCE

Procedure 1

Stage 2

use this when learner has been unable to complete three correctly of Stage 1

select No 2 out of A to H (use familiar picture)

(+)
(-)
select No 2 out of A to H (not used)
go back to Stage 1
(+)
(-)
select No2 out of B, C, D, E (not used)
go to Stage 1
(+)
(-)
go to Stage 3
show No 2 of A to H

until three consecutively

correct

If the learner is successful in Stage 1, but cannot complete 3 correct in a row at Stage 2, then READ OFF TABLE FOR CARD NO 1 AT THE APPROPRIATE DISTANCE

Stage 3

use this when the learner has been able to do two in a row successfully from Stage 4. Or else, the learner may have been correct for three consecutive from Stage 2.

select No 3 out of A to H (use familiar picture)

(+)
(-)
select No 3 out of A to H (not used)
go back to Stage 2
(+)
(-)
select No 3 out of B, C, D, E (not used)
go to Stage 2
(+)
(-)
go to Stage 4
show No 3 of B,C, D or E

until three consecutively

correct

If the learner is successful in Stage 2, but cannot complete 3 correct in a row at Stage 3, then READ OFF TABLE FOR CARD NO 2 AT THE APPROPRIATE DISTANCE

Procedure 1

Stage 5

use this when learner has been able to complete three correctly of Stage 4, but has been unable to do three in a row from Stage 7.

select No 5 out of A to H (use familiar picture)

(+)
(-)
select No 5 out of A to H (not used)
go back to Stage 4
(+)
(-)
select No5 out of B, C, D, E (not used)
go to Stage 4
(+)
(-)
go to Stage 6
show No3 of B,C, D or E

until three consecutively

correct

If the learner is successful in Stage 4, but cannot complete 3 correct in a row at Stage 5, then READ OFF TABLE FOR CARD NO 4 AT THE APPROPRIATE DISTANCE

Stage 6

use when the learner has completed three in a row successfully from Stage 5.

Or else, the learner was able to do only two in a row successfully in Stage 7.

select No 6 out of A to H (use familiar picture)

(+)
(-)
select No 6 out of B,C,D or E
go back to Stage 5
(+)
(-)
select No 6 out of B, C, D, E (not used)
go to Stage 5
(+)
(-)
go to Stage 7
show No 6 of B,C, D or E

until three consecutively

correct

If the learner is successful in Stage 5, but cannot complete 3 correct in a row at Stage 6, then READ OFF TABLE FOR CARD NO 5 AT THE APPROPRIATE DISTANCE

If the learner was successful in Stage 6, but could not complete three in a row for Stage 7, then READ OFF TABLE FOR CARD NO 6 AT THE APPROPRIATE DISTANCE

Procedure 2

Stage 1

select No 0 out of A to H (one card only) This is returning to the very large card with which the learner has been familiarised.

(+)
(-)
select No 0 of another from A to H
return to Preparation
(+)
(-)
select No 0 out of B, C, D, E (not used)
return to Preparation
(+)
(-)
go to Procedure 1, Stage 1
return to Preparation

If the learner is successful in this Procedure 2, but cannot complete Procedure 1, Stage 1, then READ OFF TABLE FOR CARD NO 0 AT THE APPROPRIATE DISTANCE