title: Discriminant construct validity of ImPACT™: a companion study.
abstract: In a previous analysis of ImPACT scores relative to traditional neuropsychological tests (NP) and experimental tasks (Maerlender et al., 2010 ) we demonstrated convergent construct validity for the primary ImPACT test-score composites. A complete analysis of discriminant validity was not undertaken at that time. Here, test scores from the 54 collegiate football and hockey players were re-analyzed to specifically address the discriminant validity of the ImPACT™ composite scores using a multiply operationalized correlation matrix of multi-trait multi-method data. In the method used here, discriminant validity is determined by obtaining non-significant correlations between a target score when correlated with the average of the other trait measurements (multiply-operationalized multi-trait-mono-method analysis). Results showed that the ImPACT™ Verbal Memory (p = .044), Visual Memory (p = .006), and Visual Motor Speed (p = .000) scores were highly correlated with composites of the other scores, while the Reaction Time composite demonstrated adequate discriminant validity (p = .145). In comparison all of the NP composites showed good discrimination (all p-values >.05, except for Reaction Time p = .05). Thus the apparent lack of discriminability between three of four composite scores in this sample raises questions about using ImPACT™ composite scores to support specific construct-oriented interpretations. Taken together, the discriminant and convergent construct validity properties of ImPACT™ indicate construct sensitivity, but limited construct specificity.
authors: Department of Psychiatry, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA. Art.Maerlender@dartmouth.edu
authors: A
authors: A
authors: Maerlender
authors: L
authors: L
authors: Flashman
authors: A
authors: A
authors: Kessler
authors: S
authors: S
authors: Kumbhani
authors: R
authors: R
authors: Greenwald
authors: T
authors: T
authors: Tosteson
authors: T
authors: T
authors: McAllister
mesh_terms: D000328:Adult; D001924:Brain Concussion / Q000175:diagnosis* / Q000523:psychology; D001930:Brain Injuries / Q000175:diagnosis* / Q000523:psychology; D005538:Football; D006688:Hockey; D006801:Humans; D008568:Memory / Q000502:physiology; D009483:Neuropsychological Tests; D011930:Reaction Time / Q000502:physiology; D011795:Surveys and Questionnaires