A METHODOLOGY FOR INTERFACE DESIGN FOR OLDER

ADULTS

Mary Zajicek

Department of Computing, School of Technology, Oxford Brookes University, Wheatley Campus,

Oxford OX33 1HX, UK

Keywords: User models, interface design patterns, design methodology, universal accessibility, older adults, speech

systems, memory support, strategies at the interface.

Abstract: This paper puts forward a new design method based upon Alexandrian patterns for interface design for

particular user groups. The author has created a set of interface design patterns for speech systems for older

adults with the aim of supporting the dynamic diversity in this group. The patterns themselves reflect a

significant body of research work with this user group uncovering important information about how they

interact with speech systems. The design knowledge embedded in these patterns is therefore closely linked

to knowledge about the user and enables interface designers to clarify which users are excluded from their

software.

1 INTRODUCTION

This paper is concerned with a new methodology for

interface design for older adults using speech

systems, where carefully describing the users for

whom the system is defined will promote a better fit

between user and system.

The paper outlines the characteristics of older

adults as computer users and introduces the idea of

patterns to encapsulate design recommendations for

speech systems for this user group. Older adults to a

greater or lesser degree experience memory

impairment and a reduction in their ability to build

strategies at the interface, characteristics which are

modeled within the patterns.

The paper discusses the challenge of complying

with legislation which promotes software

accessibility for all user types and patterns are

suggested as providing a useful framework within

which software developers can analyse their

prospective user group in this regard.

Eight interface design patterns are analyzed in

terms of the user models they implicitly and

explicitly encapsulate, and also in terms of the users

they disadvantage.

2 WHY WOULD WE WANT TO

MODEL USERS’ ABILITIES?

Recently significant legislation has been introduced

in the US and UK aimed at encouraging designers to

ensure that software does not exclude certain user

groups. Age related impairments older adults often

exclude older adults from the use of standard

software. For example the print may be to small or

the multi-tasking interface may rely to heavily on

good memory or their ability to build complex

strategies in order to use the software.

A better understanding of older adults as users

through modeling their attributes will enable

interface designers to clarify which users are

excluded by their software.

3 THE ORIGIN OF INTERFACE

DESIGN PATTERNS

The idea for patterns and pattern language

originated in the domain of architecture; with the

publication more than twenty years ago of

Christopher Alexander’s book The Timeless Way of

Building (Alexander, 1979). He proposed that one

could achieve excellence in architecture by learning

and using a carefully defined set of design rules, or

Zajicek M. (2004).

A METHODOLOGY FOR INTERFACE DESIGN FOR OLDER ADULTS.

In Proceedings of the Sixth International Conference on Enterprise Information Systems, pages 81-88

DOI: 10.5220/0002611000810088

 SciTePress

patterns: and although the essence of a beautifully

designed building is hard to define the application of

patterns for room design etc can contribute to the

design of the whole.

A pattern describes an element of design

possibly together with how and why you would

achieve it. For example Alexander created patterns

which describe ways of placing windows in a room

and designing a porch which achieves a successful

transition between inside and outside a building.

These include textual descriptions and diagrams or

photos (Alexander, 1977).

Patterns for human-computer interface design

were first discussed in the late nineties, and

currently there exist a range of different pattern

forms. Some pattern builders choose a purely

narrative approach such as those found in the Design

of Sites (Van Duyne et al, 2002) whereas others are

more structured. Martin van Welie for example sets

out patterns under the headings Problem and

Solution Van Welie, 2002) A comprehensive list of

pattern forms can be found at Sally Fincher’s

Pattern Form Gallery (Fincher, 2003).

The pattern form used in this paper, is based on

Jennifer Tidwell’s UI Patterns and Techniques

(Tidwell, 2002) where the pattern has four sections,

Use When, Why, How, and Examples. A fifth section

entitled Tradeoffs has been included from the claims

approach, as there are always tradeoffs when

designing speech dialogues and these should be

made explicit.

A full day workshop, ‘Perspectives on HCI

Patterns: Concepts and tools’ at CHI 2003 was

attended by several of the pattern developers

referenced above, where they came up with the

pattern Language Markup Language

(PLML)(Fincher, 2003) which promises to provide a

generic pattern format.

4 THE OLDER ADULT AS A USER

Adults as they get older experience a wide range of

age related impairments including loss of vision,

hearing, memory and mobility, the combined effects

of which contribute to loss of confidence and

difficulties in orientation and absorption of

information. Significantly, age related impairments

affect people at different rates and even any one

individual from day to day. The need for Design for

Dynamic Diversity to accommodate this dynamic

diversity of ability in older adults was first proposed

by Newell and Gregor (Newell & Gregor, 2000) and

is demonstrated in interface design by Gregor

Newell and Zajicek (Gregor et al, 2002).

Furthermore, gathering interface requirements

from older adults requires considerable skill and

understanding of the user group. Newell and Gregor

also proposed (Newell & Gregor, 2000) that

standard User Centered Design techniques, which

rely on relatively homogeneous user groups for user

testing, should be replaced by User Sensitive

Inclusive Design, which seeks out diversity, in order

to ensure that systems are truly usable by older

adults result.

In summary then interface design for older

adults is more complex than for standard groups,

making optimum interface design more difficult to

achieve. It is therefore particularly important that

instances of design which work well for older adults

should be carefully documented and passed on for

other designers to use.

5 ADVANTAGES OF INTERFACE

DESIGN PATTERNS FOR

OLDER ADULTS

Guidelines provide a useful form of ‘advice’ for

designers and are necessarily generalized for a range

of applications. However the information embedded

in the guideline has been distilled either from a form

of craft knowledge, or theory or through

experimentation. If the guideline comes with the

‘reason’ attached together with an example of the

use of the guideline, the designer is a stronger

position to utilize the information.

The W3C, Web Access Initiative Guidelines

(Web Access Initiative Guidelines, 1999), which

were developed for Web designers so that they

could make their Web pages more accessible for

non-standard users, are accompanied by the reasons

for the guidelines, which enables the designer to be

aware of who she or he is excluding if they do not

follow the guidelines.

Designers therefore, especially those designing

systems for older adults, would benefit from access

to the information, experimental or otherwise, that

gave rise to the guideline.

Academic papers of course exist which describe

the experiments from which the guideline was

distilled, but these contain more information than

the designer requires. The argument here is that the

information relevant to good design practice should

be set out in a structured and informative way for

easy access by the interface designer.

Interface designers are rarely older adults

themselves and therefore have no concept of how it

would feel to access a computer when you are

experiencing the combined effects of memory, sight,

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and mobility loss coupled with reduced confidence

that comes with slower processing of visual, spatial

and verbal information. Furthermore, the dynamic

diversity of ability in older adults poses particular

challenges for interface designers.

A robust set of design patterns with a linking

language is therefore a particularly important

requirement for those designing systems for use by

older adults. A set of clear and informative patterns

together with information on how the patterns may

be used together in a system i.e. the pattern

language, would enable interface designers to access

best practice and help them to create sympathetic

and successful designs for older adults.

Importantly the patterns will reflect the

experience of older adults through experimentation

and observation, which the designers themselves are

lacking. This in itself will nurture good design and

provide a framework in which mistakes need not

happen.

6 EXAMPLES OF INTERFACE

DESIGN PATTERNS

Patterns for speech systems possess different

properties compared with the more visually

orientated graphical user interface patterns of

Tidwell and van Welie (Tidwell, 2002),(Van Welie,

2002), and indeed the architectural patterns of

Alexander (Alexander, 1977). Speech dialogues use

two forms of input, speech and keypad, and output

in the form of a speech message. The usability of

the dialogue hinges on its structure and the quality

of the output messages. Patterns relevant to speech

systems therefore must include those concerned with

the construction of output messages, and also those

related to dialogue structure.

This section presents several patterns which deal

with the quality of output messages in speech

systems for older adults, and can be formed in either

pre recorded or synthetic speech. They are

categorized according to function, Menu Choice

Message, Confirmatory Message, Default Message,

Context Sensitive Help Message, Talk Through

Message, and Explanation Message together with

the dialogue structure patterns Error Recovery Loop

and Partition Input Message. This is not a complete

list of patterns for speech systems for older adults

and can be developed further with additions and

refinements.

6.1 Menu Choice Message

This pattern encapsulates design knowledge derived

from experiments carried out with older adults using

the voice Web browser BrookesTalk which offers a

menu selection of functions in a Voice Help

message which talks novice users through their

interaction with the browser (Zajicek & Morrissey,

2003).

It was found that older adults were confused by

long messages with many options and that they

remembered more information from short messages.

This phenomena was nor seen in younger people.

Older adults also tend to remember the first and the

last elements of a menu better.

Users were found to respond more favorably to

key press menu selections expressed by mnemonic

letter keys such as A for address, compared with

function keys which caused much confusion.

Finding letters on the keyboard was a major problem

for older people using the voice Web browser.

Pattern name: Menu Choice Message

Use When: When the range of choices offered in

the dialogue is small. Large numbers

of choices should be broken up into

sub menus. Keep the message as short

as possible.

Why: Experiments show that older

adults are confused by long

messages and forget the possible

options or remember only the first

or last.

How: Short messages offering at most

three selections should be used

only with very well defined

options where the user using pre-

existing knowledge (not strategies

that are worked out at the time)

can see easily which of the

selections will lead them to their

goal. Example 1. demonstrates

how this can be done. When there

are three options, place the most

commonly selected options last

and first. Use mnemonic letters to

identify menu items for key press

entry, as in Example 2.

Example: 1. “Would you like to

deposit or withdraw money?”,

rather than ‘Would you like to

perform a credit or debit transfer?”

2. “You have no page loaded.

Would you like to

Enter an address, press A

Perform a search, press S

A METHODOLOGY FOR INTERFACE DESIGN FOR OLDER ADULTS

Tradeoffs: Menus usefully group end goals in a

speech dialogue, and the smaller the

menu the greater the number of

interactions that will be needed to

reach the end goal. The tradeoff is that

reducing the number of options in the

menu lengthens the interaction.

Despite this drawback, experiments

carried out with the VABS (Zajicek et

al, 2003) showed that the short

messages approach was most

successful with older adults.

6.2 Confirmatory Message

The importance of confirmatory messages was

demonstrated during experiments carried out with

older adults using the voice Web browser

BrookesTalk (Zajicek & Morrissey, 2001). Here

confirmation was produced by a personal helper

who answered yes or no to users’ questions about

their interaction. In the domain of speech dialogues

the principle of confirmatory action is expressed in

confirmatory messages that reassure the user that the

interaction is going well.

Pattern name: Confirmatory message

Use when: After the user has input data, or made

a choice or performed some other

action that they might not be sure of.

Why: To confirm that data has been

input correctly or to draw the users

attention to the progress of the

dialogue. Research has shown that

user confidence can be increased

by confirmatory action and can aid

the construction of conceptual

models.

How: After a data input event try to arrange

for the output of a confirmatory

message that contains the input data.

In Example 1. the words in italic

represent input data that has been

embedded in a confirmatory sentence.

The message confirms that the system

still ‘knows’ that it is talking to Mary

and mentions 7 pm so that the user can

check the input. The words evening

and appointment serve to frame the

concept of the reminder. Confirmatory

messages can also be used as in

Example 2. to confirm that the

dialogue is proceeding satisfactorily.

Example: 1. ‘Mary you have

successfully booked a call

reminder at 7 pm on the evening

before your appointment”

2. “You have successfully

logged on to the Voice Activated

Booking System and have asked

for a call reminder for your

appointment on Wednesday the 8

November. What time would you

like your call reminder?”

Tradeoffs: Confirmatory messages increase

the user’s confidence in their

interaction and aid the

construction of conceptual models

of the speech system. The tradeoff

is between increasing confidence

and adding to the length of the

interaction. Confirmatory

messages demand yet more

attention of the user and can be

irritating to confident users.

Research has shown however,

especially for systems designed

primarily for first time users, that

confirmatory messages should be

used.

6.3 Default Input Message

Default input messages proved to be very useful in the

VABS system where users’ input reminder call times were

not recognized. Users were usually happy with the default

time of 7 pm for a reminder call as shown in Example 1.

Pattern name: Default Input Message

Use when: When a user is required to input data

which has been misrecognised or

when the user has failed to understand

that data must be input. This can be

used only when the input data is

relatively imprecise and a default

which would just about do is possible

as in Example 1.

Why: Because the system requires some

input data in order to continue the

interaction, or where the user has

consistently avoided inputting the

required data and is likely to terminate

the interaction.

How: The default input message should

appear when an input has been

misrecognised a certain number of

times.

Example: 1. “Would 7 pm on the evening before

your appointment be a good time for a

reminder call?”

ICEIS 2004 - HUMAN-COMPUTER INTERACTION

Tradeoff: The default input is possibly not the

input that the user intended and they

may or may not be satisfied with it.

The possibility of not being satisfied is

the tradeoff against the frustration of

trying several times to enter the

correct input or leaving the interaction

with the task incomplete.

6.4 Context Sensitive Help Message

The VABS features several help areas within the

dialogue. Users can say Help at any time during

their interaction and a message, which is specifically

relevant to the area of the dialogue they are currently

using, will be output. Context sensitive help was

invoked several times in the VABS [16] and was

considered to be very useful.

Pattern name: Context Sensitive Help Message

Use when: When help in the context of the

current task would be useful.

Why: This message is a direct response to a

user asking for help which maps

closely to human-human dialogues

when help is requested, and represents

the most efficient way in which help

can be provided. Context is important

as it ensures that the message will be

as short as possible as the message

will contain only information relevant

to the task in hand. Older adults

experience difficulty in absorbing

spoken information, and this type of

message will provide only information

which is necessary at the time.

How: Identify areas in the interaction which

relate to identifiable tasks and create

explanatory messages for each task.

Arrange for an input of Help to trigger

the relevant context sensitive help

message.

Example: 1. “This system uses voice

recognition to understand your

commands that should be spoken

clearly. Giving your name helps the

system to locate your current sessions

and gives you access to more

functions. You need to contact the

center during office hours to register

your name”.

2. “This system is designed to

offer users the ability to book or

cancel a computer taster session.

Speak your commands clearly and try

to use the words given in the

question”.

Tradeoffs: There are no direct usability tradeoffs.

This is the best way to provide help.

Unfortunately some older adults forget

that they have the option to ask for

help so alternative methods which do

not require the user to take the

initiative, must be used as well.

The only tradeoff is in the extra

programming effort required to set up

the help areas and messages.

6.5 Talk Through Message

Experiments with Voice Help for BrookesTalk

showed that speech output that talks older adults

through their interaction could enable people to use

software where they hadn’t been able to use it

before (Zajicek & Morrissey, 2001).

Pattern name: Talk Through Message

Use when: When it would be helpful to be told

where you are in the interaction and

what you can do next.

Why: Older adults find difficulty in

building strategies at the interface,

mainly because this activity relies

on short-term memory. Memory

loss means that it is difficult to

remember what you did last time

and to build up a model of how the

interaction works.

How: Where a new task is about to be

tackled, talk through messages

should be inserted to help with

orientation to the new process. It

is best to arrange for more

competent users to switch off the

messages when they are no longer

needed.

Example: 1. ‘You have arrived at the

point where you tell us when you

would like to come for your IT

Taster Session. Sessions run from

10:30 to 15:30 every hour. Please

say something like ‘ten thirty’ to

see if the session is available”.

Tradeoffs: Talk through messages irritate

confidant users and slow them

down. They slow down even

novice users and make for more

speech output to listen to, but are

considered to be most worthwhile

for older adults.

A METHODOLOGY FOR INTERFACE DESIGN FOR OLDER ADULTS

6.6 Explanation Message

Older adults find speech interaction confusing.

While younger people can adapt to the ways

computers behave older people find it more difficult.

Any explanation of what is happening can be useful.

Pattern name: Explanation Message

Use when: Use when the dialogue is behaving

in a non-intuitive way or in a way

that does not map onto usual

human-human dialogue.

Why: Interaction with a speech dialogue

is often not intuitive to older

adults, so it should explain itself

as much as possible.

Example: 1. “There will be a short

delay while your name is found on

our database”

Tradeoff: Extra messages make the dialogue

longer. The tradeoff is between

making the dialogue longer or

making it clearer.

6.7 Error Recovery Loop

Errors and error recovery represent the main

usability problem for speech systems. Standard

menu driven systems often start with a long set of

instructions in a bid to avoid errors happening.

Older users are not able to remember these

messages, which also slow down the dialogue,

rendering them useless. The pattern described here

directs designers to embed instructions in an error

recovery loop: in effect to wait for the error to

happen and then try to recover it.

This approach is most useful in dialogues which

are used mostly by experienced users who are

unlikely to require any instruction and will if they

use the dialogue successfully never have to listen to

an error recovery message.

Pattern name: Error Recovery Loop

Use when: When errors in data input are likely to

occur.

Why: Because older adults cannot

remember lengthy preliminary

spoken instructions about data

input. It is best to let them try to

input data and if it goes wrong

invoke an error recovery message.

How: Count how many times a data input

occurs and on each count invoke an

increasingly detailed error recovery

message. In the examples below

Example 1. simply gives instructions

for efficient input, but the more

detailed Example 2. provides

information about which might help

the user work better with the system.

Example: 1. “Your name has not been

recognized. Please speak slowly

and clearly into the telephone.

2. “The system is trying to

match your name against the

names it holds in the database.

Please try to speak your name in

the same way that you did when

you registered for the Voice

activated Booking System.

Tradeoffs: This form of error recovery does

not prepare the user in advance for

possible errors, as they have to

create the error before it is

invoked. The tradeoff is against

providing long instructions before

the user embarks on a task.

6.8 Partitioned Input Message

The interaction paths taken through the VABS

system by older adults was compared with the

optimum path for each task (Zajicek et al, 2003) It

was found that data input tasks showed the greatest

deviation from the optimum route and this was

because of misrecognition of utterances.

Misrecognition of input causes considerable

frustration in speech interaction and often leads to

abandonment of the dialogue.

The Partitioned Input Messages in effect

perform binary chops on the possible entry data

(Brownsey et al, 1993) For example when a time

for a reminder call is required instead of being asked

to enter the time, the user would be asked ‘Would

you like your reminder call in the morning or

afternoon?’ as normally occurs when the session

organizer sets up the reminder call. If the answer

were morning the system would then respond

‘Before eleven o’clock or after?’ The dialogue

would continue to halve the search area until a time

is selected.

Pattern name: Partitioned Input Message

Use when: Use for any discrete input data which

has up to sixteen possible values.

Sixteen values requires four questions

be asked to reach the correct value.

More than sixteen values would

require too many questions.

This message type is particularly

useful when the required input

might be confusing. Example 1.

tries to cope with IT Taster

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Sessions on the VABS which are

held on the half hour, while most

users suggest a time on the hour if

asked for input (they also ignore

instructions asking them to use the

half hour)

Why: This message replaces data input

which is the most difficult part of

speech dialogues. It is extremely

error prone and older adults find

difficulty in recovering from

errors.

How: Set up messages that divide the

number of possible input in two

each time as shown in Example 1.

Example: 1.

(i) “Would you like to attend for

taster sessions in the morning or

afternoon of Wednesday 7

June?”

(ii) “Would you like to come

before or after 11 in the

morning?”

(iii) “Would you like to come at

11.30 or 12.30?”

Tradeoff: This method takes longer than

direct data input but the tradeoff is

that it reduces the frustration of

misrecognition.

7 PATTERNS AND USER

BEHAVIOUR

Eight interface design patterns are analyzed in terms

of the user models they implicitly and explicitly

encapsulate, and also in terms of the users they

disadvantage.

Figure 1 sets out the patterns described above

with reference to the user models they support and

which users are disadvantaged by the pattern. With

the following key:

A – Models dynamic diversity

B – Models memory impairment

C – Models strategy building impairment

D – Good HCI design for all users

E – Could slow down younger users

Pattern Name

A B C D E

Menu Choice Message X X X

Confirmatory Message X X

Default Input Message X X

Context Sensitive Help X X X X

Talk Through Message X X X

Explanation Message X X X

Error Recovery Loop X X X X

Partitioned Input X X X

Figure 1: Properties of the patterns

With this categorization in place together with

the patterns themselves inexperienced software

designers can reference the patterns of the user

groups they support.

Such designers will be able to see easily to what

degree they are addressing concerns of universal

accessibility and also be aware of the tradeoff in

supporting one user model while at the same time

disadvantaging another. For example we can see in

Figure 1 that some interface design patterns that are

useful for older adults lead to sub-optimal design for

younger users.

Most importantly of all designers will be able to

search out those design patterns which provide the

optimal solution by supporting dynamic diversity

and hence all users.

8 CONCLUSIONS

Explicit information about the accessibility of

particular software design features by different

sectors of society is able to support those who are

required to make challenging design decisions

concerning design for universal access, and who

need to be aware of which users will be excluded

from their software.

The legislative demand for interface design for a

wider proportion of society will complicate the

design decisions that software developers will have

to make and in these cases the use of patterns

categorized according to user model can be of great

benefit.

ACKNOWLEDGMENTS

The author would like to thank Age Concern

Oxfordshire for their valuable support for the work

described above.

A METHODOLOGY FOR INTERFACE DESIGN FOR OLDER ADULTS

REFERENCES

Alexander, C., 1979, The Timeless Way of Building,

Oxford University Press.

Alexander, C., Ishikawa, S., Silverstein, M., 1977, A

Pattern Language: Towns, Buildings, Construction,

Oxford University Press.

Brownsey K. Zajicek M. Hewitt J., 1994, A structure for

user oriented dialogues in computer aided telephony,

Interacting with Computers 6(4), 433 – 449.

Fincher, S., 2003, CHI 2003 Workshop Report, Interfaces

No. 56, Journal of the BCS HCI Group.

Fincher, S., 2003, HCI Pattern-Form Gallery,

http://www.cs.ukc.ac.uk/people/staff/saf/patterns/galle

ry.html, (last accessed 23.4.3).

Gregor, P., Newell, 2002, A., Zajicek, M., Designing for

Dynamic Diversity – interfaces for older people,

Proceedings of 5th ACM/SIGAPH Conf. on Assistive

Technologies.

Newell A.F. & Gregor P., 2000, User Sensitive Inclusive

Design – in search of a new paradigm, Proc A.C.M.

Conference on Universal Usability, Washington, DC

Nov. pp39-44.

Tidwell, J., 2002, UI Patterns and Techniques, http://time-

tripper.com/uipatterns/about-patterns.html (last

accessed 22.4.3).

Van Duyne, D, Landay, J., Hong, J., 2002, The Design of

Sites: Patterns, principles and processes for crafting a

customer-centered web experience, Addison Weseley.

Van Welie, M., Interaction Design Patterns,

http://www.welie.com/patterns/index.html, (last

accessed 12.5.3), 2002.

Web Access Initiative Guidelines, 1999,

http://www.w3.org/TR/WCAG10/, (last accessed

12.5.3).

Zajicek M. & Hall, S., 2000, Solutions for elderly visually

impaired people using the Internet, In S. McDonald,

Y. Waern, G. Cockton (eds) People and Computers

XIV – Usability or Else!, Proceedings of HCI 2000, pp

299 – 307

Zajicek M., Morrissey W., 2001, Speech output for older

visually impaired adults, Proceedings of IHM-HCI

503 - 513

Zajicek M., Morrissey, W., 2003, Multimodality and

interactional differences in older adults, Special Issue

“Multimodality: a Step Towards Universal Access’ of

Universal Access in the Information Society,(ed. N.

Carbonell) Springer.

Zajicek M., Wales, R., Lee, A., 2003, Towards

VoiceXML Dialogue Design for Older Adults, In

Palanque P., Johnson P., O’Neill E (eds) Design for

Society. Proceedings of HCI 2003

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