Comparison of refractive findings obtained by the Bausch and Lomb IVEX and by conventional clinical refraction

The Bausch and Lomb IVEX (Integrated Vision Examination System) is a computerized refractor, designed for both subjective and objective refraction and binocular vision testing. Using a double-masked protocol, subjective refraction findings were obtained on 40 subjects by means of both IVEX and conventional clinical refraction. Although for most subjects IVEX spherical equivalent findings varied by no more than 0.25 or 0.50 D from conventional refractive findings, for some subjects IVEX findings yielded more minus or less plus than conventional refractive findings by as much as 1.00 or 1.25 D.