Table 4 Prediction of hospital mortality by the IDSA/ATS minor criteria
RuleROC (95% CI)Sensitivity (%)Specificity (%)PPV (%)NPV (%)RR (95% CI)
IDSA/ATS minor criteria
⩾10.65 (0.62 to 0.69)98.432.420.199.123.17 (7.45 to 72.03)
⩾20.79 (0.76 to 0.82)95.662.630.698.825.71 (12.77 to 51.75)
⩾3*0.82 (0.79 to 0.86)81.482.945.296.312.11 (8.53 to 17.20)
⩾40.71 (0.67 to 0.76)49.793.055.291.56.46 (5.08 to 8.20)
⩾50.63 (0.58 to 0.68)27.398.373.588.76.49 (5.24 to 8.04)
⩾60.56 (0.51 to 0.61)11.5100.0100.086.77.54 (6.53 to 8.70)
70.51 (0.46 to 0.55)1.1100.0100.085.46.85 (5.99 to 7.84)
PSI class
⩾II0.59 (0.55 to 0.63)100.017.017.2100.0Not applicable†
⩾III0.68 (0.64 to 0.71)99.536.221.299.781.46 (11.46 to 579.23)
⩾IV*0.77 (0.74 to 0.80)96.257.928.398.925.06 (11.87 to 52.91)
V0.77 (0.73 to 0.82)68.386.646.894.17.87 (5.95 to 10.42)
CURB-65 score
⩾10.63 (0.59 to 0.67)97.828.419.198.714.57 (5.45 to 38.91)
⩾20.74 (0.71 to 0.78)89.159.227.496.98.86 (5.65 to 13.91)
⩾3*0.72 (0.68 to 0.77)61.283.338.892.55.20 (3.98 to 6.79)
⩾40.62 (0.57 to 0.67)27.396.758.888.55.12 (4.03 to 6.50)
50.53 (0.49 to 0.58)6.6100.0100.086.17.19 (6.26 to 8.27)
  • ATS, American Thoracic Society; CI, confidence interval; CURB, confusion, urea nitrogen, respiratory rate, blood pressure; IDSA, Infectious Diseases Society of America; NPV, negative predictive value; PPV, positive predictive value; PSI, Pneumonia Severity Index; ROC, receiver operating characteristic area under the curve; RR, relative risk.

  • *Widely accepted thresholds to define low-risk versus high-risk patients.

  • †Not applicable owing to negative predictive value of 100%.