Table 2

HIDATq screening sensitivity/specificity table

HIDAT screeningCTTBI
True positive (TP)605
False positive (FP)627682
False negative (FN)10
True negative (TN)10511052
HIDAT positive (TP+FP)687687
HIDAT negative (FN+TN)10521052
Total17391739
Sensitivity % (TP/TP+FN)98.4% (90.0–99.9)100% (46.3–100)
Specificity % (TN/TN+FP)62.6% (60.3–64.9)60.7% (58.3–62.9)
Positive predictive value % (TP/TP+FP)8.7% (6.8–11.1)0.7% (0.3–1.8)
Negative predictive value % (TN/TN +FN)99.9% (99.4–99.9)100% (99.0–100)
  • HIDATq, Head Injury Discharge at Triage questionnaire; TBI, traumatic brain injury.