Table 3 Sensitivity, specificity, positive predictive value, and negative predictive value of the total number of observed signs (two or more, three or more, four or more) that led to the diagnosis of concussion

Number of signs present, concussion present

37

18

8

Number of signs present, concussion absent

75

38

10

Number of signs absent, concussion present

23

42

52

Number of signs absent, concussion absent

21

58

86

Sensitivity (95% CI)

0.62 (0.52–0.71)

0.30 (0.21–0.40)

0.13 (0.07–0.20)

Specificity (95% CI)

0.22 (0.16–0.28)

0.60 (0.55–0.67)

0.90 (0.86–0.94)

Positive predictive value (95% CI)

0.33 (0.28–0.38)

0.32 (0.22–0.43)

0.44 (0.23–0.68)

Negative predictive value (95% CI)

0.48 (0.35–0.61)

0.58 (0.52–0.64)

0.62 (0.60–0.65)