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

## TL;DR

This study shows that a simple single-question scale about nighttime urination can effectively assess the severity of urinary symptoms in men.

## Contribution

The NSQS is introduced as a simplified, valid alternative to the IPSS for evaluating LUTS severity.

## Key findings

- The NSQS achieved a 0.75 area under the ROC curve for distinguishing moderate/severe from mild LUTS.
- Thresholds of ≥2 and ≥3 nocturia episodes per night showed significant diagnostic value for moderate/severe LUTS.

## Abstract

Objective: This study evaluates the efficacy of the Nocturia Severity Quality Score (NSQS) as a simplified tool for assessing the severity of lower urinary tract symptoms (LUTS) in men, comparing it to the International Prostate Symptom Score (IPSS), the established standard.

Methods: We conducted a cross-sectional analysis on 697 men aged ≥40 from two urban urology clinics in Brazil. Participants completed both the IPSS and the NSQS, the latter consisting of a single question assessing nocturia frequency on a scale from 0 to 4. Diagnostic accuracy was evaluated using receiver operating characteristic (ROC) curve analysis to compare the NSQS against the IPSS.

Results: The NSQS effectively distinguished between moderate/severe and mild/asymptomatic LUTS, achieving an area under the ROC curve of 0.75 (95% CI: 0.72-0.79). NSQS thresholds of ≥2 and ≥3 episodes per night corresponded to increased likelihoods of moderate to severe LUTS, with significant diagnostic value despite varying sensitivities and specificities.

Conclusion: The NSQS provides a valid, efficient alternative to the IPSS for the initial assessment of LUTS severity in men.