Final version of the Distance Randot Stereotest: normative data, reliability, and validity

Area of Science:

• Ophthalmology
• Vision Science
• Pediatric Optometry

Background:

• Distance stereoacuity assessment is crucial for strabismic patients, particularly those with intermittent exotropia.
• The Distance Randot Stereotest was developed to provide an easily administered, quantitative measure of distance stereoacuity in children.
• Previous studies reported on the testability, validity, and normative data of a prototype version.

Purpose of the Study:

• To report normative and validity data for the final, commercially available version of the Distance Randot Stereotest.
• To evaluate the test's reliability and its ability to differentiate between normal and strabismic individuals.

Main Methods:

• The final version of the Distance Randot Stereotest was administered to 156 normal volunteers (ages 2-40) and 77 strabismic patients (ages 4-62).
• Test-retest reliability data were collected for the final version of the stereotest.
• Both prototype and final versions were administered to assess score correlation.

Main Results:

• The final version demonstrated normative scores similar to the prototype, with 96% of normal subjects scoring ≤100 arcsec.
• Test-retest reliability was high, with identical results in 82% and results within one disparity level in 100% of cases.
• Among strabismic patients, 62.3% exhibited abnormal stereoacuity, and constant strabismus was strongly associated with nil stereoacuity (95% of cases).

Conclusions:

• The Distance Randot Stereotest exhibits low variability and high test-retest reliability in normal subjects.
• There is minimal overlap in scores between normal controls and strabismic patients, indicating good discriminant validity.
• The test serves as a sensitive measure of binocular sensory status, valuable for monitoring strabismus progression or surgical recovery.