Nasal endoscopy is recommended for diagnosing adults with chronic rhinosinusitis.

ObjectiveTo assess the diagnostic value of nasal endoscopic findings in adults suspected of chronic rhinosinusitis.Data SourcesPubMed, EMBASE, and the Cochrane Library.Review MethodsA comprehensive search was performed up to March 5, 2013. Articles that assessed the diagnostic value of nasal endoscopy in adults suspected of chronic rhinosinusitis were included. For selected articles, the study design was assessed for directness of evidence and risk of bias. Prevalence, positive, and negative predictive values were extracted from reported data.ResultsOut of 3899 unique publications, we included 3 diagnostic studies with a high directness of evidence and a low or moderate risk of bias for data extraction. They showed a prevalence of chronic rhinosinusitis (diagnosed with computed tomography) of .40 to .56. Compared with posterior probabilities we found an added value for ruling in chronic rhinosinusitis by a positive nasal endoscopy of 25% to 28% and an added value for ruling out chronic rhinosinusitis by a...