thatapproach to diagnosing blindness and visual impairment in children hasn't been used for a few years, for good reason.
edit: this is good though "With charts of the recommended and more modern design, the literal application of the SSA criterion is that the standard is met when no letters at all can be read at the 20/160 level or smaller. However, the common practice has been and remains testing acuity with charts that have no intermediate sizes between 20/100 and 20/200. As it has been most commonly applied, this means that the SSA standard is met when no letters at all can be read at the 20/100 size or smaller. We are not recommending a change from the criterion for Impairment of Central Visual Acuity. We do, however, recommend standardization of chart design, which would raise policy issues for SSA. "
edit edit: a lot of that is valid, but a lot is about 10 years behind or so. Not wrong, there is just newer research. And I'm going to shut up now, because I'm the biggest nerd on the planet.
(edit: this is good though "With charts of the recommended and more modern design, the literal application of the SSA criterion is that the standard is met when no letters at all can be read at the 20/160 level or smaller. However, the common practice has been and remains testing acuity with charts that have no intermediate sizes between 20/100 and 20/200. As it has been most commonly applied, this means that the SSA standard is met when no letters at all can be read at the 20/100 size or smaller. We are not recommending a change from the criterion for Impairment of Central Visual Acuity. We do, however, recommend standardization of chart design, which would raise policy issues for SSA. "
edit edit: a lot of that is valid, but a lot is about 10 years behind or so. Not wrong, there is just newer research. And I'm going to shut up now, because I'm the biggest nerd on the planet.
gracielou,
Wed 1 Oct 2003, 8:19,
archived)