Reliability of near stereoacuity tests: Titmus, Randot, TNO, and Frisby

The purpose of this paper was to assess the reliability of four standard stereotests and evaluate them by means of their failure rates. Near stereoacuity in 200 healthy young volunteers (24 +/- 8 years), was measured with Titmus, Randot, TNO, and Frisby tests. The stereoacuity provided by these four tests were evaluated. Stereoacuity by the normal population, with a limit of 85% of the people, rises 70 with Randot and 120" with TNO independently of gender. Females achieve 80 with Titmus and 30 with Frisby and males reach 140 and 40 with Titmus and Frisby respectively. Failure rates lower than 10% were obtained by all the tests. This study finds differences among stereoacuity measured with different tests and recommends performing, at least, two types of test to evaluate each person.