Visual Functioning of Individuals and Communities: A Conceptual Framework

The prevalence of visual impairment and blindness increases dramatically with advancing age. The major diseases that cause visual impairment and blindness, specifically cataract, macular degeneration, and glaucoma, are age-related. The number of visually impaired Americans older than 40 years is projected to double by 2030. Half of all cases of blindness may be preventable. Research in the area of vision has developed into ophthalmologically defined silos that follow specific diseases or study subparts of the eye. To overcome the limitations of current subspecialty conceptualization of vision problems, it is necessary to develop new models that can expand the current research paradigms in new directions. This review paper details literature within a conceptual model to explain the increases in visual impairment, the age and other demo- graphic disparities in prevalence, and the lack of vision screening, treatment, and rehabilitation. At the core of the conceptual framework are the twin phenomena of vision health as perceived by the individual and vision health as clinically-measured. Other domains of the framework include adaptation, vision demands, quality of life, and cues to using vision services such as access to care and social support. The framework incorporates multiple demographic, behavioral, and social factors that influence the vision health of individuals and communities. Areas of future research include population-based study of the knowledge, attitudes, and practices regarding vision health among both individuals and providers and multi-pronged interventions aimed at the individual, provider, organizational, and community levels to improve visual function.