One-week test-retest reliability of nine binocular tests and saccades used in concussion

Abstract

BackgroundTests of binocular vision (BVTs) and ocular motility are used in concussion assessment and management.PurposeTo determine the one-week test-retest reliability of 9 binocular vision tests (BVTs) and a test of saccades proposed for use in concussion management.Study DesignProspective test-retest.MethodsWe examined the one-week test-retest reliability of 9 BVTs in healthy participants: 3D vision (gross stereoscopic acuity), phoria at 30cm and 3m, ability of eyes to move/fixate in-sync (positive and negative fusional vergence at 30cm and 3m, near point of convergence and near point of convergence – break [i.e. double vision]) and 1 ocular motor test, saccades.ResultsWe tested 10 males and 10 females without concussion and a mean age of 25.5 (4.1) years. The intraclass correlations suggest good reliability for phoria 3m (0.88) and gross stereoscopic acuity (0.86), and moderate reliability for phoria 30cm (0.69), near point of convergence (0.54), positive fusional vergence (0.54) and negative fusional vergence (0.66) at 30cm, and near point of convergence - break (0.64). There was poor reliability for saccades (0.34), and both positive and negative fusional vergence (0.49 and 0.43, respectively) at 3m. Limits of agreement (LoA) were best for saccade (±34%) and worst for phoria 30 cm (±121%) and ranged from ±58% to ±70% for 7 of the 8 other tests. The LoA for phoria at 3m were uninformative because measurements for 18 of 20 participants were identical.ConclusionWe found test-retest reliability of the BVTs and saccades ranging from poor to good in healthy participants, with the majority being moderate.Clinical RelevanceFor these vision tests to be clinically useful, the effect of concussion must have a moderate to large effect on the scores of most of the tests.What is known about the subjectConcussions may affect some parts of visual function1-week test-retest reliability for most visual tests is under-studiedWhat this study adds to existing knowledgeWe provide intra-class coefficients and limits of agreement for 10 different visual function tests commonly conducted by clinicians in patients with concussion.