Pneumonia and influenza together ranked as the eighth leading cause of death in the United States and led to over 1 million hospital admissions in 2009, with pneumonia accounting for the majority of the deaths.1 While most cases will resolve with treatment, patients admitted to the intensive care unit have mortality rates as high as 37%.2 Prior studies show that timely initiation of appropriate antibiotic therapy is associated with decreased mortality.3 In addition to its clinical and public health importance, pneumonia is also one of several conditions targeted in “pay for performance” approaches, and hospitals' performance on certain measures of pneumonia quality is publicly reported. Thus, establishing an accurate and timely diagnosis of this illness is imperative.