Table 2

Clinical characteristics of patients with different level of risk of complications after mild head injury

All cases (n = 5578)Low risk (n = 1676)Medium risk (n = 1200)High risk (n = 2702)
Significantly different from all cases: *p<0.05; **p<0.01; ***p<0.001.
IQR: interquartile range.
Sex (males)3105 (55.7%)990 (59.1%)735 (61.2%)***1380 (51.1%)***
Age (years, mean (SD))48.0 (24.2)32.8 (13.0)***32.0 (13.2)***64.5 (22.3)***
Injury type
    Crash2819 (50.6%)942 (56.2%)760 (63.3%)1117 (41.3%)
    Occupational406 (7.3%)219 (13.1%)***113 (9.4%)74 (2.7%)***
    Accidental2040 (36.6%)382 (22.8%)***244 (20.4%)***1414 (52.3%)***
    Assault191 (3.4%)86 (5.1%)*42 (3.5%)63 (2.3%)
    Sport84 (2.0%)42 (2.5%)***32 (2.7%)***10 (0.4%)***
    Other38 (0.7%)5 (0.3%)**9 (0.8%)24 (0.9%)***
Injury to admission time (min, median (IQR))60 (40–110)60 (40–120)60 (40–120)60 (40–100)