Table 1.
Subject Demographics and Neuropsychological Measures
| Trauma control Mean ± sd | Mild TBI Mean ± sd | Pa | |
|---|---|---|---|
| Demographics | |||
| Age (year) | 35.6 ± 14.1 (n = 23) | 35 ± 12 (n = 19) | 0.884 |
| Education (year) | 15 ± 3 (n = 23) | 16 ± 2 (n = 19) | 0.222 |
| Injury-to-imaging interval (day) | 31 ± 20 (n = 23) | 15 ± 10 (n = 19) | 0.003* |
| Estimated verbal intellectual ability (WRAT4 reading score) | 98 ± 8 (n = 23) | 105 ± 6 (n = 19) | 0.011* |
| Neuropsychological measures | |||
| Attention (CPT) | |||
| DISRT (ms) | 369 ± 43 (n = 18) | 405 ± 50 (n = 18) | 0.022* |
| VIGRT (ms) | 402 ± 72 (n = 20) | 405 ± 54 (n = 18) | 0.648 |
| Memory | |||
| CVLT | 53 ± 12 (n = 23) | 53 ± 11 (n = 19) | 0.708 |
| SD (number of words recalled) | 11 ± 3 (n = 23) | 12 ± 3 (n = 19) | 0.827 |
| LD (number of words recalled) | 12 ± 3 (n = 23) | 12 ± 3 (n = 19) | 0.957 |
| Executive function | |||
| DKEFS1 (s) | 19.3 ± 3.7 (n = 23) | 18.7 ± 3.8 (n = 19) | 0.895 |
| DKEFS2 (s) | 24 ± 5 (n = 20) | 27 ± 6 (n = 19) | 0.073 |
| DKEFS3 (s) | 26 ± 6 (n = 21) | 26 ± 7 (n = 19) | 0.371 |
| DKEFS4 (s) | 60 ± 16 (n = 21) | 59 ± 15 (n = 18) | 0.720 |
| DKEFS5 (s) | 21 ± 5 (n = 21) | 21 ± 5 (n = 19) | 0.894 |
| Mood | |||
| Beck score | 2 ± 2 (n = 21) | 3 ± 3 (n = 16) | 0.053 |
| ANXTR score | 26 ± 6 (n = 23) | 26 ± 5 (n = 16) | 0.817 |
| Post-concussion symptoms | |||
| RPQ-3 | 0.39 ± 0.84 (n = 23) | 3.05 ± 3.10 (n = 17) | <0.001* |
| RPQ-13 | 0.83 ± 1.67 (n = 23) | 9.33 ± 11.34 (n = 17) | 0.001* |
| RPQ-TOT | 0.43 ± 1.34 (n = 23) | 10.44 ± 13.73 (n = 17) | 0.001* |
Two-tailed Student's t-test excluding outliers outside 1.5 IQR and adjusted for estimated verbal intellectual ability (WRAT4 Reading Standard Score).
Bold numbers denote p < 0.05 significant level.
IQR, interquartile range; n, sample size excluding outliers; sd, standard deviation; TBI, traumatic brain injury; WRAT4, Wide Range Achievement Test 4th edition, reading subtest; CPT, Continuous Performance Test; DISRT: Distractibility trial, CPT, reaction time (in milliseconds); VIGRT, Vigilance trial, CPT, reaction time (in milliseconds); CVLT, California Verbal Learning Test, second edition, total words recalled trials 1 to 5; SD, number of words recalled on CVLT-II short-delay free recall; LD, number of words recalled on CVLT-II long-delay free recall; DKEFS, Delis–Kaplan Executive Function System, Trail Making Test; DKEFS1, visual scanning trial of Trail Making Test, seconds to complete task; DKEFS2, number sequencing trial of Trail Making Test, seconds to complete task; DKEFS3, letter sequencing trial of Trail Making Test, seconds to complete task; DKEFS4, number letter switching trial of Trail Making Test, seconds to complete task; DKEFS5, motor speed trial of Trail Making Test, seconds to complete task; Beck, Beck Depression Inventory, second edition (BDI-II), total score out of 63; ANXTR: Trait Anxiety score, total score range 20 to 80; RPQ-3, Rivermead post-concussion questionnaire, the sum of the first three items; RPQ-13, Rivermead post-concussion questionnaire, the sum of the items 4 to 16; RPQ-TOT, Rivermead post-concussion questionnaire, the sum of all items.