Patient-Reported Measures of the Effects of Vision Impairments and Low Vision Rehabilitation on Functioning in Daily Life.

The quantification of vision impairments dates to the mid-nineteenth century with standardization of visual acuity and visual field measures in the eye clinic. Attempts to quantify the impact of vision impairments on patients' lives did not receive clinical attention until the close of the twentieth century. Although formal psychometric theories and measurement instruments were well developed and commonplace in educational testing, as well as in various areas in psychology and rehabilitation medicine, the late start applying them to clinical vision research created a vacuum that invited poorly developed and poorly functioning instruments and analytic methods. Although this research is still burdened with legacy instruments, mandates by regulatory agencies to include the patients' perspectives and preferences in the evaluation of clinical outcomes have stimulated the development and validation of self-report instruments grounded in modern psychometric theory and methods. Here I review the progress and accomplishments of applying modern psychometrics to clinical vision research.