Reliability of EP3OS symptom criteria and nasal endoscopy in the assessment of chronic rhinosinusitis – a GA ² LEN study

Abstract

Our findings suggest that a symptom-based definition of CRS, according to the epidemiological part of the EP3OS criteria, has a moderate reliability over time, is stable between study centers, is not influenced by the presence of allergic rhinitis, and is suitable for the assessment of geographic variation in prevalence of CRS.