Abstract

This paper describes the development of a questionnaire for assessing an individual's problems in performing visual activities typical of everyday life. We were particularly interested in an instrument which would be useful with the elderly population, because eye disease is especially prevalent in this age group (Leibowitz et al., 1980), and even in the absence of significant eye disease, older adults can still experience losses in visual function (Owsley & Sloane, 1990). This type of instrument could be useful from a number of perspectives. First, in many research settings it is desirable to have some sort of metric for assessing the extent to which a subject is having problems in everyday visual tasks. Ideally it would be best to obtain performance measures on the visual tasks under study, but the reality is that this is not possible in many studies. Thus, researchers often resort to asking subjects about their self-perceived problems in performing the activity in question, but without a valid and reliable instrument, subjects' answers are often useless from a scientific standpoint. Examples of settings in which a psychometrically solid questionnaire might be helpful are: evaluating the effects of a treatment or procedure (e.g., cataract surgery) on visual functioning; assessing how self-perceived visual difficulties relate to an adverse outcome such as a vehicle crash or a fall; and gathering information about visual tasks especially difficult for certain subpopulations of older adults (e.g., those with age-related maculopathy). A second way a questionnaire may be useful is in collecting epidemiological data on visual problems in the elderly population. Epidemiological studies on eye health and visual functioning are costly, and from the standpoint of actually carrying out the project, these studies are not particularly challenging or stimulating for research oriented clinicians (see Ederer, 1983). Coren and Hakstian (1987; 1988) have suggested that a suitably constructed questionnaire could be a much cheaper way to obtain some types of epidemiological data. A third way in which a questionnaire instrument might be useful is in developing hypotheses about the mechanisms underlying vision problems in the elderly. When visiting the laboratory or clinic, older adults often articulate visual problems, and a questionnaire could provide them the opportunity to do so in a systematic fashion. Fourth, a questionnaire might also be useful to clinicians since subjective information from the patient can yield clues about an undiagnosed disease process or condition.

© 1992 Optical Society of America