PURPOSE: To examine the impact of a unique evidence-based clinical pathway on six outcomes of care in patients hospitalized for community-acquired pneumonia (CAP). METHODS: A retrospective cohort study of CAP patients discharged between January 1999 and December 2001, from 31 Adventist Health System institutions nationwide. A total of 22,196 records were available for multivariate analyses. Odds ratios (OR) for the outcomes were calculated and stratified by a unique severity score. The severity score ranged from I to 5, where 5 indicated the most severe condition. RESULTS: Pathway patients were significantly less likely to die in-hospital compared with non-pathway patients in four of the five severity strata (OR in severity level 1 = 0.37; 95% confidence interval [CI], 0.20-0-70). In all severity strata, pathway patients were approximately twice as likely as non-pathway patients to receive blood cultures and appropriate antibiotic therapy. Among patients who were classified as severity level 1, pathway patients experienced an 80% reduction in the odds of respiratory failure requiring mechanical ventilation (OR = 0.20; 95% CI, 0.12-0.33). CONCLUSIONS: Patients who were placed on pneumonia clinical pathway care were much more likely than non-pathway patients to have favorable outcomes of care. (C) 2004 Elsevier Inc. All rights reserved.