Percussion of the chest re-visited: a comparison of the diagnostic value of ausculatory and conventional chest percussion.

Percussion of the chest is thought to be insensitive in detecting small or deeply situated chest lesions. A newer technique, ausculatory percussion, has been reported as having a far higher sensitivity. In a controlled blind study the diagnostic value of conventional chest percussion compared with ausculatory percussion was defined using the chest x-ray as a gold standard. The prevalence of disease in 100 lung fields was 26%. The majority of lesions were not detected by either technique resulting in very low sensitivities of 15.4% for conventional percussion and 19.2% for ausculatory percussion. A positive result with ausculatory percussion was twice as likely to be false as true (positive predictive value 31.2%). The technique did not add to the diagnostic value of conventional percussion. Both techniques have major limitations. Patients with suspected lung disease still require chest x-ray examination if percussion is normal.