1. INTRODUCTION
One of the hallmarks of a civilised society is its commitment to ensuring that all of its citizens can play a full part in its life, and that none are excluded by reason of birth, belief, aptitude or circumstance. Exclusion takes many forms and must be countered in many different ways. Undertaken by the Centre for Research in Library and Information Management (CERLIM) at the Manchester Metropolitan University, the Non-Visual Access to the Digital Library (NoVA) project was concerned with exploring the exclusion from access to information which can all too easily occur when individuals do not have so-called "normal" vision. Our domain in this project is digital library services, and our concern is to improve understanding of the differences between the information searching behaviour of sighted and visually-impaired users in such environments and thus to contribute to the development of more accessible services.
The rapid development of networked information and communications technologies provides opportunities for radical changes in the services which can be delivered to all information users, including those who need to use "accessible" formats and systems in order to overcome visual or other disability. During usability testing carried out as part of the REVIEL project in which blind people accessed a variety of online resources, it became apparent that navigation is a major problem within digital library systems. A good example is the use of frames in a web environment to enable the user to perform complex selections across categories. A sighted person navigates between frames in a complex, non-linear manner which displays strong parallelism. A non-sighted person using audio or Braille output has to navigate linearly within one frame at a time, and may need to backtrack a long way (again in a linear manner) in order to reach the desired point (and then maybe track forward again). Although REVIEL provided the initial impetus for investigating this area, NoVA was designed to investigate it in depth.
Of course, much work is continuing to make interfaces accessible - witness, for example, the work of the World Wide Web Consortium's Web Accessibility Initiative (W3C WAI) - but there is little current work on how blind and visually impaired people navigate interfaces, and in particular on how the serial paradigm of a blind person's search maps onto the parallelism displayed by so many interfaces. Work on accessibility concentrates on transcribing text (or replacing images etc. with text) when the problem may in fact be much deeper. Work on information seeking behaviour and the use of interfaces assumes visual capabilities, which blind and visually impaired people often do not possess.
The overall objective of the NoVA Project, therefore, was to develop understanding of serial searching in non-serial digital library environments, with particular reference to retrieval of information by blind and visually impaired people.
The term visually impaired is generally used to describe "all those who have a seeing disability that cannot be corrected by glasses" (Hopkins 2000). This includes people who are entitled, under UK regulations, to register as blind or partially sighted. A blind person can be registered as either blind or partially sighted, although registration as blind rarely means total loss of sight. The measure is based on the "quality of distance and side vision as measured by consultant ophthalmologists" (Hopkins 2000).
The sample of visually impaired sample who took part in the NoVA project will be referred to in this report as "visually impaired" whether or not they had total or partial sight loss. This is in no way an attempt to over-simplify eye conditions, or to try and define the sample as one homogenous group. It is merely an attempt to simplify the terminology used in the report and to concentrate on the key issue of navigation where "standard" visual cues are not available. It is acknowledged that exploration of the variations in behaviour imposed by different types of impairment would require a different, and more extensive, study.
[ Previous Section: Abstract ] [ Next Section: Adapting to Visual Impairment ]