ERCIM News No.28 - January 1997

Interface Adaptation in a Teleworking Environment for Disabled People

by Henrike Gappa and Stefanie Mermet

TEleworking for DISabled People (TEDIS) is a publicly funded research and development project of the research group on Human-Computer Interaction of GMD. Cooperation partners are the Forschungsinstitut Technologie-Behindertenhilfe and Siemens Nixdorf (Project: Computers Help to Heal). Since the beginning of the project, the State-of-the-Art of Interface Technology for the Handicapped has been investigated and recorded in a database called STAITHY (STate of the Art of Interface Technology for the Handicapped). TEDIS is targeted at implementing a suitable teleworking environment for disabled end-users. This refers to usability issues concerning the human-computer interface as well as to investigating the social impact of home-based teleworking for disabled end-users.

At present, there are about 100 million elderly and 50 million handicapped people living in Europe. Recent official surveys reveal 6.4 million severely handicapped people only in Germany. This tendency is increasing. Modern telecommunication technologies offer many possibilities for special needs adjustment. Thus, severely handicapped as well as elderly people can be enabled to live a self-determined life and take part in social and economic affairs. For example, telecommunication technology can compensate for an often prevailing lack of physical mobility, which is detrimental to the vocational integration of handicapped people.

Unfortunately, however, technological progress does not necessarily imply enhancement of applicability of information technology. In general, special needs of handicapped end-users are not equally taken into consideration by system designers. Handicapped people are usually not included into design processes. Therefore, products are often inaccessible due to small but - with regard to certain disabilities - crucial shortcomings.

For this reason, since the beginning of the project, the state-of-the-art of suitable technologies was investigated with regard to telecooperation systems and human- computer interfaces adaptable to certain disabilities. As a result, the database STAITHY was developed. The underlying framework of STAITHY has a two-factorial design. On the first dimension, it generally differs between seven types of disabilities (physical, hard of hearing, deaf, low vision, blind, speaking, language or cognitive). The second dimension relates to the so called IFIP-Model of Human-Computer Interfaces, which is being promoted by the International Federation for Information Processing (IFIP).

According to the IFIP-model, the end-user interacts with a computer system through different interface layers. For our purposes we considered only the interface layers which are of relevance for adaptations to certain disabilities: the terminal (input/output), the functional- and the communication interface. The retrieval functionality of the database is based on the described classification pattern. One query for example looks for all output interfaces adapted to blind users, another looks for all communication interfaces for the deaf and the like. The current web-based version of the database focuses on prototype-products still under development at universities and research centers for rehabilitation technology.

TEDIS teleworkers prefer working at home.

Most of the interface technologies listed in the database are evaluated by comments of disabled information technology experts. For the future, we strive for special needs user-interfaces by involving end-users with different disabilities into experimental research environments, being set up by GMD's Human Factors Lab. Currently, special needs interface evaluation is most basically guided by the software-ergonomic criteria of the EVADIS II guideline (Evaluation of Dialog-Systems).

All in all, STAITHY reveals a strong need for inexpensive and generic interface adaptation for end users with special needs. Therefore, in the teleworking domain the main objective of the TEDIS project is to develop a prototypical teleworkstation, which can easily be adapted to the different needs of disabled end-users and inexpensively be reproduced by industry.

Telework for severely handicapped people

As part of the TEDIS field-trial, the internet-based telecooperation environ-ment BSCW (Basic Support for Cooperative Work) was installed to manage the teleworking process for two severely physically disabled teleworkers. BSCW is developed by GMD and available free of charge by common internet browsers (

In order to ensure the suitability of the BSCW-teleworkstation, principles of participative systems design have been applied. This referred to technical aspects as well as issues of usability.

Based upon data gained by structured usability-interviews, the current focus of the project is to implement a generic human computer interface for accessing Internet, which can be adapted to a variety of different needs of handicapped as well as elderly people. At present, complete accessibility of an internet browser by keyboard is under development as a first feature, since operating a mouse causes many problems for motor-impaired, blind or visually impaired end-users.

During our exploration of usability issues it became obvious that English as the dialogue-language of the telecooperation system BSCW causes an important obstacle in handling the system. Although it is almost taken for granted that English is the prevailing dialogue-language in the world of computers, it became apparent, that due to this circumstance a lot of people, particularly within the group of elderly and disabled people, are excluded from this world. Thus, the development of a German BSCW version is on its way.

The project lays further stress upon investigating the social significance of home-based telework. It is to counteract the issue, that handicapped people may become isolated in a world of technical devices which they are able to handle but which seclude them from social life. In this context, information about the social environment of the two teleworkers, their self-awareness, their expectations towards vocational life as well as their attitude towards telework is gathered and evaluated. So far, both teleworkers clearly prefer working at home mainly because this offers the possibility of individually determinable working-hours and a relaxed working-atmosphere. Social aspects of working out-of-home like making informal contacts to colleagues are less important to them. They rather lay stress upon a challenging type of work according to their abilities. In this latter context, the impact of providing additional communication channels (eg videoconferencing) on job enrichment and job satisfaction of the two disabled teleworkers will especially be investigated.

At present, the organization of the teleworking process, the workflow and time-management as well as task-related communication are investigated, since these factors are considered to be crucial for the vocational integration of mobility impaired people by telework.

Please contact:
Henrike Gappa ­ GMD
Tel: +49 2241 14 2393

Stefanie Mermet ­ GMD
Tel: +49 2241 14 2044

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