Towards evidence based emergency medicine: best BETs from the Manchester Royal Infirmary. Detection of pneumoperitoneum on erect chest radiograph.

A short cut review was carried out to establish whether a normal erect chest radiograph excludes the diagnosis of perforated abdominal viscus. Altogether 37 papers were found using the reported search, of which two presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are shown in table 1. A clinical bottom line is stated.