title: Statistical procedures for determining the extent of cognitive change following concussion.
abstract: Neuropsychological (NP) testing is now often used to help to determine if the cognitive function of a concussed athlete has declined. The NP test score after concussion is compared with the baseline test score. Many clinicians simply subtract one from the other and make a clinical decision about the significance or otherwise of the resulting "difference score". Such techniques are inadequate, as they fail to account for the many factors that may confound interpretation of serially acquired cognitive test scores. This is a review of a number of alternative approaches used in other areas of medicine for differentiating "true" changes from changes caused by these confounding factors. A case example is used to illustrate the effect that the statistical approach may have on clinical decision making.
authors.affiliation: Center for Neuroscience, University of Melbourne, Parkville, Victoria, Australia. acollie@cogstate.com
authors.forename: A
authors.initials: A
authors.lastname: Collie
authors.forename: P
authors.initials: P
authors.lastname: Maruff
authors.forename: M
authors.initials: M
authors.lastname: Makdissi
authors.forename: M
authors.initials: M
authors.lastname: McStephen
authors.forename: D G
authors.initials: DG
authors.lastname: Darby
authors.forename: P
authors.initials: P
authors.lastname: McCrory
mesh_terms: D000328:Adult; D001265:Athletic Injuries / Q000150:complications / Q000523:psychology*; D001924:Brain Concussion / Q000523:psychology*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology / Q000523:psychology; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D038223:Post-Concussion Syndrome / Q000209:etiology / Q000523:psychology; D012044:Regression Analysis