title: Heterogeneity in Trail Making Test performance in OEF/OIF/OND veterans with mild traumatic brain injury.
abstract: This study used cluster analysis to examine variability in Trail Making Test (TMT) performance in a sample of Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn (OEF/OIF/OND) veterans referred for mild traumatic brain injury (mTBI). Three clusters were extracted, two of which were characterized by level of performance and the third with a unique performance pattern characterized by slow performance on the TMT B (Low B). Clusters did not differ on demographic or psychiatric variables. The Above Average cluster had better performance on measures of processing speed, working memory, and phonemic fluency compared with the Low B cluster. Results suggest that a subset of patients with mTBI perform poorly on TMT B, which subsequently predicts poorer cognitive functioning on several other neuropsychological measures. This subset may be vulnerable to cognitive changes in the context of mTBI and multiple comorbidities while a number of other patients remain cognitively unaffected under the same circumstances.
authors.affiliation: Oklahoma City Department of Veteran Affairs Medical Center, Oklahoma City, OK, USA.
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Thaler
authors.forename: John F
authors.initials: JF
authors.lastname: Linck
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Heyanka
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Pastorek
authors.forename: Brian
authors.initials: B
authors.lastname: Miller
authors.forename: Jennifer
authors.initials: J
authors.lastname: Romesser
authors.forename: Anita
authors.initials: A
authors.lastname: Sim
authors.forename: Daniel N
authors.initials: DN
authors.lastname: Allen
mesh_terms: D000328:Adult; D055826:Afghan Campaign 2001-; D001930:Brain Injuries / Q000523:psychology*; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D054542:Iraq War, 2003-2011; D008297:Male; D014145:Trail Making Test; D014728:Veterans / Q000523:psychology*
keywords: Assessment; Mild cognitive impairment; Statistical methods