Abstract

Background: Obstructive sleep apnea (OSA) is a prevalent yet underdiagnosed sleep-related breathing disorder with significant cardiovascular and metabolic consequences. Screening questionnaires offer accessible preliminary assessment tools, but their diagnostic accuracy requires validation against polysomnography (PSG).
Objective: To evaluate and compare the diagnostic performance of the Berlin Questionnaire (BQ) and Epworth Sleepiness Scale (ESS) in screening for OSA, using PSG as the gold standard.
Methods: This cross-sectional observational study was conducted at a tertiary sleep disorders center over 18 months. A total of 248 adult participants with suspected OSA underwent comprehensive evaluation using BQ and ESS, followed by overnight laboratory-based PSG. OSA severity was classified based on Apnea-Hypopnea Index (AHI): mild (5-14.9 events/hour), moderate (15-29.9 events/hour), and severe (≥30 events/hour). Diagnostic accuracy parameters including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for both screening tools.
Results: Among 248 participants (mean age 46.3±12.7 years, 64.5% male), PSG confirmed OSA in 182 (73.4%) subjects. The Berlin Questionnaire demonstrated sensitivity of 78.6%, specificity of 65.2%, PPV of 83.7%, and NPV of 56.8% for detecting OSA (AHI ≥5). The ESS showed sensitivity of 54.4%, specificity of 75.8%, PPV of 82.5%, and NPV of 44.6%. BQ exhibited superior sensitivity (p=0.001), while ESS showed higher specificity (p=0.042). Both tools demonstrated reduced sensitivity in mild OSA cases compared to moderate-to-severe disease.
Conclusion: The Berlin Questionnaire demonstrates superior sensitivity for OSA screening, making it more suitable for initial case identification. The ESS, with higher specificity, may better complement clinical evaluation. Combined utilization of both instruments may optimize screening effectiveness, though neither tool can replace polysomnography for definitive diagnosis.