Mean (SD) or n (%) | Early season (n = 418) | Midseason (n = 2078) | Late season (n = 98) | Total (n = 2594) | F/χ2 | p value* |
---|---|---|---|---|---|---|
Demographic factors | ||||||
 Age | 15.25 (1.19) | 15.31 (1.23) | 15.76 (1.23) | 15.3 (1.23) | 6.97 | 0.001 |
 History of concussion | 116 (27.8) | 596 (28.7) | 34 (35.4) | 746 (28.8) | 2.29 | 0.32 |
 Years playing at HS level | 1.65 (1.90) | 1.73 (1.96) | 2.13 (2.40) | 1.73 (1.97) | 3.88 | 0.21 |
 Gender (male) | 418 (100) | 2074 (99.90) | 98 (100) | 2590 | 1.00 | 0.61 |
 Handedness (right) | 350 (83.37) | 1792 (86.23) | 84 (85.71) | 2226 (85.81) | 2.81 | 0.59 |
 Country (USA) | 418 (100) | 2068 (99.50) | 98 (100.00) | 2584 (99.61) | 2.49 | 0.65 |
 ADHD | 58 (13.86) | 282 (13.57) | 12 (12.24) | 352 (13.57) | 0.20 | 0.91 |
 Learning disorder | 36 (8.6) | 196 (9.43) | 10 (10.20) | 242 (9.32) | 0.33 | 0.85 |
 Days since injury | 4.09 (1.69) | 4.24 (1.68) | 4.18 (1.73) | 4.21 (1.68) | 1.52 | 0.22 |
Treatment history | ||||||
 Headaches | 44 (10.50) | 260 (12.90) | 12 (12.80) | 316 (12.18) | 1.08 | 0.58 |
 Migraines | 36 (9.10) | 146 (7.30) | 6 (6.40) | 188 (7.24) | 1.72 | 0.42 |
 Epilepsy/seizures | 0 (0.00) | 18 (0.90) | 0 (0.00) | 18 (0.69) | 4.50 | 0.11 |
 Brain surgery | 0 (0.00) | 4 (0.20) | 0 (0.00) | 4 (0.15) | 0.99 | 0.61 |
 Meningitis | 2 (0.50) | 14 (0.70) | 2 (2.10) | 18 (0.69) | 2.81 | 0.25 |
 Alcohol/substance abuse | 0 (0.00) | 2 (0.10) | 0 (0.0) | 2 (0.07) | 0.49 | 0.78 |
 Depression/anxiety | 8 (2.00) | 46 (2.30) | 2 (2.10) | 56 (2.15) | 0.15 | 0.93 |
Baseline neurocognitive and symptom scores | ||||||
 Verbal memory | 81.73 (10.31) | 82.78 (10.16) | 83.08 (10.49) | 82.62 (10.20) | 6.69 | 0.001 |
 Visual memory | 72.46 (12.95) | 74.14 (12.83) | 70.24 (13.90) | 73.74 (12.83) | 0.82 | 0.44 |
 Visual motor speed | 34.72 (6.26) | 35.19 (6.95) | 35.00 (6.14) | 35.11 (6.79) | 1.05 | 0.35 |
 Reaction time | 0.63 (0.09) | 0.63 (0.09) | 0.62 (0.08) | 0.63 (0.09) | 11.02 | < 0.001 |
 Total symptom score | 6.02 (10.60) | 4.35 (7.95) | 4.54 (8.37) | 4.54 (8.37) | 1.88 | 0.15 |