Community-acquired pneumonia: severity of illness evaluation.

Severity-of-illness assessment is now an accepted part of clinical practice and clinical research for the management of adults who have community-acquired pneumonia. Several approaches to this issue have been devised based on severity-of-illness scores or rules, some related to site of management. No single approach has been found to be superior to others, but further research into their effect on outcome in clinical practice is required. It is likely that different approaches may suit different populations and health care systems.