In Europe 90-95% of antibiotic use occurs outside hospitals, and community acquired lower respiratory tract infections (LRTI) are the leading reason for prescribing antibiotics.1 Few conditions in medicine are so controversial or have resulted in so much promiscuity in prescribing. The escalating resistance of common bacterial respiratory pathogens to antibiotics in the community2 will be contained only by reducing prescribing in everyday practice and targeting antibiotics selectively. We have known this for a long time. But it is difficult to target antibiotics appropriately, particularly in LRTI.

Several problems underlie this clinical uncertainty about which patients with LRTI benefit from antibiotics and which do not. The update on diagnosis and management of pneumonia by Hoare and Lim in this week's BMJ nicely illustrates this controversy (p 1077).3 Results of trials indicate that most patients with initially uncomplicated infection will probably have limited benefit, but this evidence is scant: the relevant …