Antibiotic treatment of acute bronchitis in smokers: a systematic review

CRD COMMENTARY: The objective of the review was clear and the inclusion criteria relating to the interventions, participants and study design were appropriate. The authors did not specify a priori inclusion criteria for the outcomes, therefore selective reporting is a possibility. One database was searched for English language studies, and the authors did not report any specific attempt to identify unpublished studies. Thus, it is possible that relevant studies could have been missed and that the findings might be influenced by publication and language bias. The quality of the included studies was appropriately assessed and study details were reported. The authors did not provide details of the original results of the included studies before the data were transformed to point estimates. A narrative synthesis was appropriate, although differences between the studies were not adequately investigated. The authors did not specify any details of how the review was conducted, so it is not possible to determine whether steps were taken to minimise bias in the review process. The most tentative interpretation of the authors' conclusions is advisable.