Computerized method of viual acuity teting: adaptation of the amblyopia treatment tudy viual acuity teting protocol

PURPOE: To report a computerized method for determining viual acuity in children uing the Amblyopia Treatment tudy viual acuity teting protocol. METHOD: A computerized viual acuity teter wa developed that ue a programmed handheld device that ue the Palm operating ytem (Palm, Inc, anta Clara, California). The handheld device communicate with a peronal computer running a Linux operating ytem and 17-inch monitor. At a tet ditance of 3 m, ingle letter can be diplayed from 20/800 to 20/12. A C program on the handheld device run the Amblyopia Treatment tudy viual acuity teting protocol. Uing thi method, viual acuity wa teted in both the right and left eye, and then the teting wa repeated in 156 children age 3 to 7 year at four clinical ite. REULT: Tet-retet reliability wa high (r = .92 and 0.95 for and right and left eye, repectively), with 88% of right eye retet and 94% of left eye retet within 0.1 logarithm of minimal angle of reolution (logMAR) unit of the initial tet. The 95% confidence interval for an acuity core wa calculated to be the core ± 0.13 logMAR unit. For a change between two acuity core, the 95% confidence interval wa the difference ± 0.19 logMAR unit. CONCLUION: We have developed a computerized method for meaurement of viual acuity. Automation of the Amblyopia Treatment tudy viual acuity teting protocol i an effective method of teting viual acuity in children 3 to 7