Characterizing the Randot Preschool stereotest: Testability, norms, reliability, specificity and sensitivity in children aged 2-11 years

Autoři: Jenny C. A. Read aff001;  Sheima Rafiq aff001;  Jess Hugill aff001;  Therese Casanova aff001;  Carla Black aff001;  Adam O’Neill aff001;  Vicente Puyat aff001;  Helen Haggerty aff002;  Kathryn Smart aff002;  Christine Powell aff002;  Kate Taylor aff002;  Michael P. Clarke aff001;  Kathleen Vancleef aff001
Působiště autorů: Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, England, United Kingdom aff001;  Newcastle Eye Centre, Royal Victoria Infirmary, Newcastle upon Tyne Hospitals NHS Trust, Newcastle upon Tyne, England, United Kingdom aff002
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224402



To comprehensively assess the Randot Preschool stereo test in young children, including testability, normative values, test/retest reliability and sensitivity and specificity for detecting binocular vision disorders.


We tested 1005 children aged 2–11 years with the Randot Preschool stereo test, plus a cover/uncover test to detect heterotropia. Monocular visual acuity was assessed in both eyes using Keeler Crowded LogMAR visual acuity test for children aged 4 and over.


Testability was very high: 65% in two-year-olds, 92% in three-year-olds and ~100% in older children. Normative values: In 389 children aged 2–5 with apparently normal vision, 6% of children scored nil (stereoblind). In those who obtained a threshold, the mean log threshold was 2.06 log10 arcsec, corresponding to 114 arcsec, and the median threshold was 100 arcsec. Most older children score 40 arcsec, the best available score. We found a small sex difference, with girls scoring slightly but significantly better. Test/retest reliability: ~99% for obtaining any score vs nil. Agreement between stereo thresholds is poor in children aged 2–5; 95% limit of agreement = 0.7 log10 arcsec: five-fold change in stereo threshold may occur without any change in vision. In children over 5, the test essentially acts only as a binary classifier since almost all non-stereoblind children score 40 arcsec. Specificity (true negative rate): >95%. Sensitivity (true positive rate): poor, <50%, i.e. around half of children with a demonstrable binocular vision abnormality score well on the Randot Preschool.


The Randot Preschool is extremely accessible for even very young children, and is very reliable at classifying children into those who have any stereo vision vs those who are stereoblind. However, its ability to quantify stereo vision is limited by poor repeatability in children aged 5 and under, and a very limited range of scores relevant to children aged over 5.

Klíčová slova:

Eyes – Children – Normal distribution – Research validity – Schools – Vision – Visual acuity – Binocular vision


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