Abstract
Abstract: :
Purpose:Visual acuity is a poor measure for cataract surgery indication or outcome. Formal scales of visual function are rarely used in everyday practice due to their length, and doctors’ informal estimates are often inaccurate, leading to unnecessary operations and dissatisfied patients. The objective of this study is firstly, to examine the relationships between importance, satisfaction, visual acuity and visual function in a sample of preoperative cataract patients; secondly, to derive and prospectively evaluate a shortened measure of visual function. Methods:Two independent samples of 111 and 121 patients were surveyed before and after surgery with regard to their visual satisfaction, trouble with vision, VF–14 visual function, overall satisfaction and importance of certain factors affecting patient satisfaction. A seven item scale of visual function derived from the first sample’s results was prospectively tested against the second sample. Distance and reading acuities were recorded from the patients’ charts. Results:The seven item measure of visual function strongly correlates with the VF–14 (r>.9) and had predictive power equal to the VF–14 for both satisfaction and trouble with vision. However, the seven items selected differ somewhat from a version developed in Helsinki. As expected, distance visual acuity was not significantly correlated with visual function, satisfaction or trouble with vision, although reading acuity was significantly correlated with both visual function (r=.31) and trouble with vision (r=.32). Conclusions:This paper offers a shortened measure of visual function which can more practically be used in everyday practice. Furthermore, regional factors matter. This study highlights the necessity of basing measurement scales upon factors important to the population in question, in order to ensure scale validity.
Keywords: cataract • clinical (human) or epidemiologic studies: outcomes/complications