Validation of a clinical prediction model for early admission to the intensive care unit of patients with pneumonia

Acad Emerg Med. 2012 Sep;19(9):993-1003. doi: 10.1111/j.1553-2712.2012.01424.x.


Objectives: The Risk of Early Admission to the Intensive Care Unit (REA-ICU) index is a clinical prediction model that was derived based on 4,593 patients with community-acquired pneumonia (CAP) for predicting early admission to the intensive care unit (ICU; i.e., within 3 days following emergency department [ED] presentation). This study aimed to validate the REA-ICU index in an independent sample.

Methods: The authors retrospectively stratified 850 CAP patients enrolled in a multicenter prospective randomized trial conducted in Switzerland, using the REA-ICU index, alternate clinical prediction models of severe pneumonia (SMART-COP, CURXO-80, and the 2007 IDSA/ATS minor severity criteria), and pneumonia severity assessment tools (the Pneumonia Severity Index [PSI] and CURB-65).

Results: The rate of early ICU admission did not differ between the validation and derivation samples within each risk class of the REA-ICU index, ranging from 1.1% to 1.8% in risk class I to 27.1% to 27.6% in risk class IV. The areas under the receiver operating characteristic (ROC) curve were 0.76 (95% confidence interval [CI] = 0.70 to 0.83) and 0.80 (95% CI = 0.77 to 0.83) in the validation and derivation samples, respectively. In the validation sample, the REA-ICU index performed better than the pneumonia severity assessment tools, but failed to demonstrate an accuracy advantage over alternate prediction models in predicting ICU admission.

Conclusions: The REA-ICU index reliably stratifies CAP patients into four categories of increased risk for early ICU admission within 3 days following ED presentation. Further research is warranted to determine whether inflammatory biomarkers may improve the performance of this clinical prediction model.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Validation Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Community-Acquired Infections / diagnosis
  • Community-Acquired Infections / mortality
  • Community-Acquired Infections / therapy
  • Critical Care / methods
  • Emergency Service, Hospital / statistics & numerical data
  • Female
  • Hospital Mortality*
  • Humans
  • Intensive Care Units / statistics & numerical data*
  • Male
  • Middle Aged
  • Patient Admission*
  • Pneumonia / diagnosis
  • Pneumonia / mortality
  • Pneumonia / therapy*
  • Predictive Value of Tests
  • Prohibitins
  • Retrospective Studies
  • Risk Assessment
  • Survival Rate
  • Time Factors
  • Treatment Outcome