Defining the Minimal Important Difference in International Prostate Symptom Score for Men with Lower Urinary Tract Symptoms Using a Patient-centered Anchor Measure

We looked at results for the International Prostate Symptom Score (IPSS), a questionnaire used to assess lower urinary tract symptoms (LUTS) in men, to determine what patients feel is a meaningful improvement in symptoms. We used data from a clinical trial that tested an app to help men in improving their LUTS. Men felt that the minimum level of improvement for a benefit was change of 5.26 points in IPSS. Men with more severe symptoms at the start of treatment required greater improvements, while men with moderate symptoms needed smaller changes. These findings may help doctors in understanding the amount of improvement in symptoms that patients feel is significant, and could guide future LUTS treatments and trials.