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1.
User needs and goals:
The first part of any assistive technology assessment, involves a detailed assessment of the users needs and goals. The user himself or herself should be the most important part of the first date of this assessment. Before thinking of the technology, types of switches, or activities, it is essential to take a long hard detailed look at the types of challenges experienced by the user, the types of activities he needs to participate in, and also his strengths and skills. Only by identifying the areas in which improved function or participation is needed, can you go on to identifying the types of assistive technology equipment and applications which may assist.
A couple of excellent resources discussing the assessment process for assistive technology in detail, are the following:
www.joyzabala.com .This web site discusses the SETT Framework for assessment in detail.
www.qiat.org The Quality Indicators for Assistive Technology Services
web site provides extensive resources related to assistive technology and assessment.
2.
Determine type of access
method:
Selection Methods for Input
It is important that a specialized assessment for adaptive
switch input is only carried out following an overall
assessment of the various options for adaptive input.
There are an enormous number of different options in terms
of input methods available to individuals with
disabilities. Types of input methods can be generally
placed into one of three different categories:
Direct select: this refers to
any method that involves selection of an item with
pointing of a finger, or any kind of pointing device such
as a head stick or palm pointer etc. Direct select
involves the choice of a specific focus or target point
with a motor movement which is directed specifically
towards the target point. Because of this immediate action
selection, direct select is almost always the selection
method of choice if it is possible for an individual,
given a range of modifications and customized options. In
almost every case, direct select will be the most
efficient, quickest method of access for those who are
able to cope with this access method. If an individual is
able to actively select items through a direct point
method, and is able to make selections accurately, this
will in most cases we the method of choice for input.
Pointing to make a choice, is one of the most normal and
natural early developmental skills learned in a young
child. As such, even for someone with a severe disability,
pointing and reaching is one of the most natural and
intuitive methods of making a selection.
Direct select, however, is not
possible for all users. It is important to look at the
many other types of input and selection methods available.
Directed selection: this
refers to a method of making choices by moving and items
or cursor around towards the selection choice. An example
of this, is the use of a joystick, mouse pointing device,
head mouse, or even some mouse control systems using
directional switch control. As the cursor, or box /
selection items on the screen is moved around towards the
desired choice, the movement is a directed movement of a
cursor to make the selection, hence the term directed
selection.
Directed selection can be a very
powerful and effective method of input for some users. In
almost all cases it is not as quick as direct select,
however for some users it may be significantly more
accurate in terms of accurate item selection compared to
direct select.
Indirect selection:
for individuals with
significant physical disabilities, indirect select often
offers a whole new way of participating in functional
activities, producing work, and participating in
communication and recreational activities which would not
otherwise be possible.
Indirect select involves the use of
hardware, which generally takes the form of adaptive
switches, used in combination with a range of equipment
such as computers and communication devices, running
different types of programs for various functions. There
are a number of different types of indirect select options
and methods:
Single switch direct response
Single switch automatic timing scanning
Intermediate two switch step scanning
Two switch step scanning
row-column,
block, inverse
Encoding
3.
Assessment of biomechanics, joint movement and switch
control sites:
See online, interactive
information about joint
movement and switch control
sites.
Some important points to
consider when selecting a joint movement and control site
for switch placement:
SMALL, CONTROLLED
MOVEMENT: The movement should be as small and
controlled as possible, using the least amount of energy
and effort. Only a small, controlled movement can be
repeated many times without causing excessive stress on
the joints or resulting in fatigue.
MOTOR LEARNING AND SKILL
DEVELOPMENT: Learning to activate and control
switches is the same as any other motor skill learning -
it requires time, many, many switch hits per day (in the
hundreds...), repetition of the same movement, and
perseverance as in learning any new physical skill.
LOW PROFILE AND
UNOBTRUSIVE: another reason for opting for smaller
switches is that the switch itself should not be 'the
activity'! The switch should become
'transparent'. It should be simply a means of
'making something happen', participating, communicating
and being involved in other activities. The switch
should be out of the way of all activities, not interfere
with placement of objects; it should not obscure visual
contact with activities or communication partners.
VISUAL TARGETS!!!: If
at all possible, the switch should be set up so that the
user can access the switch without looking for the
switch. If a user spends his time and effort looking
for the switch and trying to access it, that means visual
contact and attention is taken away from the communication
partner or activity at hand, to find and activate the
switch.
EXTENDED USE SETUPS:
For many switch users, switches are their means of access
for many activities during their day. If possible,
switch control sites and types of movements and switches
should be selected with keeping in mind the need for use
at all times. For those who need changes in switch
setups, these should be quick and easy to set up and
move. For those who need access to a switch or
switches all day, make sure those are accessible in all
environments and positions.
4.
Select type/s of switch/es:
5.
Applications - what are the activities and tasks for
participation and communication?:
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