Interexaminer repeatability of a new, modified prentice card compared with established phoria tests

Abstract

Purpose. The Howell phoria card, a new modification of the Prentice design, has no previously published validity or reliability data. The purpose of this study was to compare the interexaminer repeatability of the Howell phoria card with established tests. Method. Experienced optometrists measured the near heterophoria of 72 subjects. Heterophoria was measured in a pseudo-random order using five standardized procedures: (1) Howell phoria card continuous presentation, (2) Howell phoria card flashed presentation, (3) free-space von Graefe method, 4) Bernell Muscle Imbalance Measure (MIM) card continuous presentation, and (5) MIM card flashed presentation. Results. The von Graefe method and the..