Vision-Specific Instruments for the Assessment of Health-Related Quality of Life and Visual Functioning

Abstract

Clinically objective measures such as visual acuity or visual field provide an assessment of a patient's visual status. However such measures may not reflect the degree of visual impairment the patient experiences in his or her daily activities. Visual impairment has been shown to have negative effects on health-related quality of life (HR-QOL) and a significant impact on daily functioning, including social activities. As such, there is a growing recognition of the importance of patient-reported outcomes of visual functioning. This review examines the development and psychometric properties of 22 vision-specific instruments assessing visual functioning and/or the impact of visual impairment on HR-QOL or daily activities. Issues relevant to assessing vision-specific subjective outcomes are reviewed, with specific application of the reviewed instruments. Three instruments, the Activities of Daily Vision Scale, National Eye Institute Visual Function Questionnaire, and Visual Function Index have been well validated and widely used, but others also show promise. To fully capture the benefits of a new ophthalmology treatment (or new treatment for eye disease) a valid and reliable visual instrument, in which the psychometric performance has been demonstrated in the particular ocular condition being treated, should be utilised.

Daily functioning, problem solving and satisfaction for quality of life in visually impaired old persons

“…High internal consistency of the original instrument was found by Margolis et al [40]. The Italian version of the instrument shows comparable psychometric properties [41].…”

Low Visual Acuity is Associated with the Decrease in Postural Sway

“…© 2008 Visual perception is closely related to postural control and provides afferent feedback regarding postural sway to the cerebellum (Loughlin et al 1996;Loughlin and Redfern, 2001). Visual function is mainly evaluated via visual acuity and the visual fields (Margolis et al 2002). The former refers to the sharpness of vision, as tested with a Snellen eye chart.…”

“…The latter refers to the space or range in which objects are visible to immobile eyes. The visual field is divided broadly into central vision (viewable angle < 2.5 degree) and peripheral vision (viewable angle > 2.5 degree) based on anatomical and functional differences of the retina (Margolis et al 2002). Hence, their roles in postural control may also differ (Brandt et al 1973;Hilton et al 2003;.…”

“…These contradictory concepts may be attributed to different definitions of both types of vision among the studies and to different methods of presenting visual stimuli . In particular, the central visual field is anatomically defined as the central 2.5 degrees of the visual field (Margolis et al 2002); however, this definition varies in each study by 10 (Nougier et al 1998) to 60 degrees (Brandt et al 1973). As mentioned above, there is room for improvement with regard to the definition and the methodology.…”

Content validity of a home-based person-environment interaction assessment tool for visually impaired adults

“…Several assessment tools have been validated with visually impaired and elderly adults , as reviewed in the literature [50][51][52][53][54][55][56]. These tools can be divided into two categories: environment and daily living activities.…”