Abstract
Background Severity assessment of community-acquired pneumonia (CAP) is essential for many purposes. Among these are the microbiological confirmation strategy and choice of empirical antimicrobial therapy. However, many severity assessment systems have been developed to aid clinicians to reach reliable predictions of severe outcomes.Methods We aimed to apply nine disease severity assessment scoring systems to a large 2016 to 2021 CAP cohort in order to achieve test sensitivity, specificity and predictive values. We used intra-hospital case fatality rate and the need for intensive care therapy as outcomes. The area under the receiver operating characteristic (ROC) curve was used to display test performance.Results A total of 1.112 CAP episodes were included in the analysis, of which 91.4% were radiologically, and 43.7% were microbiologically confirmed. When intra-hospital case fatality was set as outcome, frequently used tests with few data entries typically underperformed as compared to infrequently used tests that require more comprehensive data entries. Comparable results were gained when intensive care admittance was set as outcome. The area under the receiving operating curve was 0.0955, 0.845 and 0.892 for the sequential organ failure assessment (SOFA), pneumonia severity index (PSI), and the Infectious Diseases Society of America/American Thoracic Society definitions, respectively.Conclusion CAP severity assessment remains important. Simplified scoring systems underperformed as compared to more comprehensive and sophisticated ones.