A Newer Way to Look at Bladder Symptoms: What the LURN SI-10 Measures
Bladder symptoms don't always fit neatly into one label.
You might leak when you cough, but never feel urgency. You might have no leakage at all, yet notice a weak stream, bladder discomfort, or difficulty getting started. Or several symptoms may happen together and make it hard to explain what exactly feels wrong.
Many traditional urinary questionnaires were designed around a particular condition or patient group.
The LURN Symptom Index-10, or LURN SI-10, takes a different approach.
It is a newer-generation urinary symptom questionnaire developed through a research network funded by the National Institutes of Health (NIH)'s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Rather than focusing only on overactive bladder, incontinence, or prostate-related symptoms, it was designed to capture a broader spectrum of lower urinary tract symptoms in both women and men.
That makes it particularly useful when your symptoms don't fit neatly into a single category.
Why was LURN created?
For decades, clinicians have had useful questionnaires for specific urinary problems.
The IPSS, for example, became widely used for urinary symptoms associated with BPH in men. Other questionnaires focused more heavily on women's pelvic floor disorders, urinary incontinence, or overactive bladder.
But researchers saw a limitation: people often experience several different kinds of urinary symptoms at the same time, and existing questionnaires didn't always capture the whole picture.
In 2012, NIDDK created the Lower Urinary Tract Dysfunction Research Network (LURN) to better understand lower urinary tract symptoms and improve how patients' experiences are measured.
Researchers initially developed a remarkably comprehensive 93-question assessment, known as CASUS.
They then worked backward from that large symptom library to create shorter tools that could actually be practical in research and healthcare: the LURN SI-29 for more detailed research use and the LURN SI-10 as a brief clinical assessment.
So the ten questions weren't simply chosen because ten sounded convenient.
They were distilled from a much broader effort to understand how people actually experience urinary symptoms.
What does the LURN SI-10 ask about?
LURN SI-10 asks about your symptoms during the past seven days and covers much more than frequency or urgency.
Its ten questions look at:
Urgency : Do you suddenly feel that you need to urinate?
Urgency urinary incontinence : Do you leak urine after feeling a sudden urge?
Stress-type leakage : Do you leak when you cough, sneeze, or laugh?
Leakage during activity : Do you leak during physical activity, such as exercise or lifting something heavy?
Bladder pain or discomfort : Do you experience pain or discomfort while your bladder is filling?
Difficulty starting : Is there a delay before your urine stream starts?
Weak or slow stream : Does your urine flow feel slow or weak?
Post-void dribbling : Do you notice urine dribbling after you've finished and gotten dressed?
Daytime frequency : How many times do you typically urinate while awake?
Nocturia : How many times do you typically wake up at night to urinate?
Together, those questions cover urgency, several forms of incontinence, bladder pain, voiding difficulty, frequency, nocturia, and post-urination symptoms.
That's the main reason LURN feels different from a questionnaire designed around one diagnosis.
One thing that makes LURN unusual: it was built for women and men from the start
This is more significant than it may sound.
Some older urinary symptom questionnaires originated in populations defined by sex or by a particular condition.
LURN researchers instead included both women and men throughout the development process, from early qualitative work through item testing and formal validation. Urologists and urogynecologists were both represented in the expert panel that selected the final clinical questions.
The result is a questionnaire that asks about symptoms relevant across sexes without assuming that everyone's urinary problem belongs to the same diagnosis.
For women in particular, that can be useful because urinary symptoms don't always begin and end with “Do you leak?”
Pain, urgency, frequency, nocturia, difficulty emptying, weak flow and different types of leakage can all be part of the picture.
LURN looks at more than just “incontinence”
Incontinence is actually one of LURN's strengths, but not because LURN simply asks whether you leak.
It asks how leakage happens.
Leaking after sudden urgency is different from leaking when coughing or sneezing. Leakage with physical activity is different again. Post-void dribbling can reveal another pattern.
This distinction matters because the word “incontinence” can hide several different experiences.
In a later study comparing LURN SI-10 with IPSS in 429 men with LUTS, LURN detected symptoms that IPSS does not directly capture, including post-void dribbling in 24%, urgency urinary incontinence in 13%, stress urinary incontinence in 2%, and pain in 8% of participants.
That study was conducted in men, but it demonstrates why broader questioning can uncover useful information that a more condition-specific questionnaire might miss.
What does a LURN SI-10 score mean?
The LURN SI-10 total score ranges from 0 to 38.
Higher scores generally indicate a greater overall burden or frequency of lower urinary tract symptoms.
But LURN is a little different from scores such as IPSS or OABSS.
There aren't universally established consumer categories such as 0 - X = mild / X - Y = moderate / Y - Z = severe that we would recommend using to interpret LURN SI-10 on your own.
And that is actually consistent with what makes the questionnaire useful.
The total score matters, but so does which questions are contributing to it.
Two people could have similar total scores while having completely different experiences:
One person may primarily have urgency and leakage.
Another may have weak flow and difficulty starting.
Someone else may have frequency, nighttime urination and bladder discomfort.
The same number can therefore represent different symptom profiles.
Rather than asking only, “Is my score high?”, LURN can help you ask:
“Which kinds of urinary symptoms am I actually experiencing?”
Has LURN been scientifically validated?
Yes.
The original validation study included both women and men with lower urinary tract symptoms.
LURN SI-10 correlated strongly with established urinary symptom questionnaires: its correlation with the AUA Symptom Index was 0.77 in men and 0.70 in women, while its correlation with the UDI-6 in women was 0.76.
It also performed well when researchers tested whether it could distinguish people with different levels of urinary symptom severity as defined by established measures, with ROC AUC values around 0.82 - 0.90 against AUA-SI categories and 0.84 - 0.86 against UDI-6 symptom status.
More recent studies have also validated translations of the instrument in additional populations, including Turkish, Arabic and Thai versions.
And the NIH-supported LURN program notes that some hospitals have incorporated the SI-10 into their electronic health record systems for clinical use.
Can LURN be used to measure treatment progress?
This is an area where I'd be careful not to overstate the evidence.
The LURN instruments were designed partly to improve outcome measurement, and researchers are actively studying how well they capture treatment-related change.
There is already encouraging evidence from the longer LURN SI-29.
In a prospective multicenter study of 135 men starting alpha-blocker treatment for LUTS, average LURN SI-29 scores fell from 37.0 to 22.4 after one month, alongside improvement in IPSS and urine flow. Changes in LURN and IPSS were strongly correlated. Researchers concluded that LURN SI-29 may be useful for evaluating treatment response while providing additional information about symptoms such as incontinence, post-urination symptoms and pain.
The SI-10 has also been used as an outcome measure in prospective clinical research, including studies tracking urinary symptoms after procedures.
However, unlike IPSS and OABSS, the SI-10 does not yet have a widely established minimal clinically important change that I would tell consumers to use as a treatment-success threshold.
Researchers are still working on exactly how LURN scores should be used longitudinally and what amount of change represents a meaningful clinical improvement. A prospective study integrating LURN with routine BPH care specifically lists establishing clinically meaningful differences among its objectives.
For now, that makes LURN particularly useful for building a broader baseline and seeing how your own symptom pattern changes, rather than chasing a universal target score.
LURN and a bladder diary tell you different things
This is where LURN becomes particularly useful alongside Bladderly.
LURN asks you to look back over the past seven days and describe a broad range of urinary symptoms.
A bladder diary records what actually happened during particular days:
when you urinated
how much you urinated
what and how much you drank
when urgency occurred
whether leakage happened
how often you woke at night
So LURN can help answer:
“What kinds of bladder symptoms am I experiencing?”
Your bladder diary can help answer:
“When are they happening, and what patterns can I see?”
For someone whose symptoms don't fit neatly into “OAB” or “incontinence,” that combination can be particularly useful.
Take the LURN SI-10 with Bladderly
Bladder symptoms can be difficult to explain, especially when several things seem to be happening at once.
With Bladderly, you can complete the LURN SI-10 alongside your digital bladder diary and keep a record of your urinary symptoms and everyday bladder patterns in one place.
You don't need to decide first whether your issue is “urgency,” “incontinence,” or something else.
Start by describing what's actually happening.
Over time, those details can give you a clearer baseline, help you notice changes, and make it easier to explain your experience to a healthcare professional.
The LURN SI-10 and Bladderly do not diagnose the cause of urinary symptoms or replace medical evaluation. New pain, blood in the urine, difficulty urinating, sudden changes in bladder function, or other concerning symptoms should be discussed with a healthcare professional.
References
Cella D, Smith AR, Griffith JW, et al. A New Brief Clinical Assessment of Lower Urinary Tract Symptoms for Women and Men: LURN SI-10. Journal of Urology. 2020;203(1):164–170. https://doi.org/10.1097/JU.0000000000000465.
National Institute of Diabetes and Digestive and Kidney Diseases. (2024, January 10) Lower Urinary Tract Symptoms Network (LURN): Development and Use of Improved Assessments of Urinary Symptoms. 2024.
Glaser, A. P., Helfand BT, et al. The 10-item LURN Symptom Index (LURN SI-10) Detects Additional Symptoms and Shows Convergent Validity With the IPSS in Men Presenting With Lower Urinary Tract Symptoms. Urology.171, 184–189. 2023.
Cakici MC, et al. Efficacy of Symptoms of Lower Urinary Tract Dysfunction Research Network Symptom Index-29 Questionnaire in Assessing Alpha-blocker Treatment Response in Patients With Benign Prostatic Hyperplasia: A Prospective, Multicenter, Cohort Study. Urology. 196, 249–253. 2025.
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