A systematic review included 5 studies with a total of 934 subjects. Of the 8 physical examination maneuvers evaluated, conventional percussion was the most accurate for diagnosing pleural effusion (summary positive likelihood ratio 8.7, 95% CI 2.2 to 33.8), and the absence of reduced tactile fremitus made pleural effusion less likely (negative likelihood ratio 0.21, 95% CI 0.12 to 0.37).
Comment: The quality of evidence is downgraded by inconsistency (heterogeneity of patients studied).
Weak recommendation: If dullness of percussion is observed in a patient with suspected pleural effusion, a chest radiograph or ultrasonography should be performed to confirm pleural effusion (or detect other pulmonary pathology). The strength of recommendation is downgraded by indirectness of evidence on patient outcomes.