Diagnostic Accuracy of a Nocturia Single Question Scale as a Predictor of Severity of Lower Urinary Tract Symptoms in Men

Abstract

Objectives: To evaluated the accuracy of a single question on nocturia to identify men with moderate and severe LUTS. Methods: We evaluated men aged ≥40 years who presented for medical evaluation at two different urological clinics. They completed the IPSS and the Nocturia Single Question Scale (NSQS). NSQS consists of a single question assessing nocturia frequency ranging from 0 to 4. The severity of LUTS using NSQS (index test) versus IPSS (reference standard) was assessed according to the recommendations of the Standards for Reporting of Diagnostic Accuracy Initiative. Results: The accuracy of the NSQS to discriminate patients with severe LUTS based on the ROC curve was 75% (CI 95% 73 − 82%; p < 0.001). Conclusion: Patients without nocturia or a single void/night (NSQS < 2) have low probability, while NSQS ≥ 3 has a high probability of having moderate or severe LUTS. NSQS is an acceptable alternative to the IPSS, being a fast and simple tool to identify men according to LUTS's severity.