title: Comparison of baseline-referenced versus norm-referenced analytical approaches for in-theatre assessment of mild traumatic brain injury neurocognitive impairment.
abstract: OBJECTIVE
  To examine differences between the baseline-referenced and norm-referenced approaches for determining decrements in Automated Neuropsychological Assessment Metrics Version 4 TBI-MIL (ANAM) performance following mild traumatic brain injury (mTBI).
  
  
  METHODS
  ANAM data were reviewed for 616 US Service members, with 528 of this sample having experienced an mTBI and 88 were controls.
  
  
  METHODS
  Post-injury change scores were calculated for each sub-test: (1) normative change score = in-theater score - normative mean and (2) baseline change score = in-theater score - pre-deployment baseline. Reliable change cut-scores were applied to the change and the resulting frequency distributions were compared using McNemar tests. Receiver operator curves (ROC) using both samples (i.e. mTBI and control) were calculated for the change scores for each approach to determine the discriminate ability of the ANAM.
  
  
  RESULTS
  There were no statistical differences, p < 0.05 (Bonferonni-Holm corrected), between the approaches. When the area under the curve for the ROCs were averaged across sub-tests, there were no significant differences between either the norm-referenced (0.65) or baseline-referenced (0.66) approaches, p > 0.05.
  
  
  CONCLUSIONS
  Overall, the findings suggest there is no clear advantage of using the baseline-referenced approach over norm-referenced approach.
authors.affiliation: a Naval Submarine Medical Research Laboratory , Groton , CT , USA.
authors.forename: F Jay
authors.initials: FJ
authors.lastname: Haran
authors.affiliation: b National Intrepid Center of Excellence , Walter Reed National Military Medical Center , Bethesda , MD USA.
authors.forename: Michael N
authors.initials: MN
authors.lastname: Dretsch
authors.affiliation: c Geneva Foundation , Tacoma , WA , USA.
authors.forename: Jill C
authors.initials: JC
authors.lastname: Slaboda
authors.affiliation: d Eyak Development Corporation , Arlington , VA , USA.
authors.forename: Dagny E
authors.initials: DE
authors.lastname: Johnson
authors.affiliation: e Naval Medical Center Portsmouth , Portsmouth , VA , USA.
authors.forename: Octavian R
authors.initials: OR
authors.lastname: Adam
authors.affiliation: f US Navy Bureau of Medicine and Surgery , Arlington , VA USA.
authors.forename: Jack W
authors.initials: JW
authors.lastname: Tsao
mesh_terms: D000328:Adult; D001924:Brain Concussion / Q000175:diagnosis* / Q000523:psychology; D060825:Cognitive Dysfunction / Q000175:diagnosis* / Q000209:etiology / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008889:Military Personnel / Q000523:psychology*; D009483:Neuropsychological Tests; D012015:Reference Standards; D012016:Reference Values
keywords: ANAMA; baseline; mTBI; military; neurocognitive; normative