A Comparative study of four Persian versions of sleep questionnaires for screening obstructive sleep apnea syndrome (OSAS)

Background: Diagnosis of obstructive sleep apnea syndrome (OSAS) is valuable, but it is time-consuming and expensive. Appropriate screening instruments help clinicians select high-risk individuals for further investigations. In the present study, we compared 4 popular instruments used in screening OSAS including Berlin, STOP, STOP-BANG questionnaires, and Epworth Sleepiness Scale (ESS).    Methods: A total of 250 individuals, who referred to Sleep Laboratory of Shoorideh Hospital (Tehran, Iran) for polysomnography during May 2015 to November 2015, were recruited for this cross-sectional study. In addition to taking history and physical examination, 4 screening instruments including Berlin, STOP, STOP-BANG questionnaires, and ESS were completed. Diagnosis of OSAS was established using apnea-hypopnea index (AHI) in 3 categories of mild, moderate, and severe.    Results: Severe OSAS was diagnosed in 159 (63.6%), moderate OSAS in 43 (17.2%), and mild OSAS in 41 (16.4%) of the participants, moreover, AHI was within normal range in the other 7 (2.8%). To diagnose OSAS with any severity, Berlin questionnaire was a preferable instrument, with a sensitivity of 79.8% and specificity of 71.4%, considering the cut-point value of 3.5. In addition, in cases of severe OSAS, Berlin questionnaire showed superiority over other instruments, with a sensitivity of 80.5% and specificity of 61.5% using the cut-point value of 3.5.       Conclusion: None of the 4 instruments are ideal to predict OSAS. However, considering the simplicity and availability of the instruments, Berlin and STOP-BANG questionnaires had maximum diagnostic values that helped us distinguish OSAS and severe OSAS, respectively.