Cognitive Screening Tests in Concussion: Classification Agreement and Differential Symptom Sensitivity

Area of Science:

• Neurology
• Sports Medicine
• Neuroscience

Background:

• Concussion assessment commonly uses King-Devick (KD) test, Montreal Cognitive Assessment (MoCA), and computerized batteries.
• The concordance of these cognitive tests for clinical decision-making in concussion is not well understood.

Purpose of the Study:

• To examine classification agreement among KD, MoCA, and computerized tests.
• To investigate how symptom burden and time from injury influence test concordance in concussion patients.

Main Methods:

• Retrospective analysis of 253 concussion patients (359 visits) with concurrent KD, MoCA, Neurobehavioral Symptom Inventory (NSI), and computerized test data.
• Assessed classification agreement using Cohen's kappa and Spearman correlations, stratified by symptom burden and time from injury.
• Used multivariable regression to analyze associations between symptom burden and cognitive performance, adjusting for covariates.

Main Results:

• Three-way test agreement was virtually absent (Fleiss' κ = 0.002); pairwise agreement was also slight (κ < 0.20).
• Tests agreed on impairment in only 3 of 359 visits; patients normal on all tests still reported significant symptoms.
• King-Devick (KD) and Creyos performance correlated with symptom burden, while MoCA did not. Agreement decreased with higher symptom burden.

Conclusions:

• Cognitive tests for concussion frequently disagree, impacting clinical impressions.
• KD and computerized tests reflect symptom burden, unlike MoCA, with concordance varying by symptom level and time from injury.
• Cognitive tests should be used alongside clinical judgment and physical examination, not as standalone concussion measures.