Study title

Primary care management of lower urinary tract symptoms in men: development and validation of a diagnostic and decision making aid (The PriMUS Study).

Principal / Lead Investigator
Type of study

Diagnostic accuracy study

Who is the study sponsor?

Cardiff University


More than 10% of older men experience the need to pass urine more frequently than usual and often find their sleep interrupted by having to go to the toilet during the night. Some will find that their urine flow rate has become slower, and some will experience loss of bladder control. Such problems are distressing for men, affect their work and social life, and are a common reason why men visit a general practitioner (GP) with over 60,000 attendances yearly across the UK.

They firstly need reassurance that they are not suffering from cancer or any other sinister medical condition. GPs follow established procedures when considering signs of cancer or these more serious conditions, but they have no easily available assessment tools to identify other more common causes of lower urinary tract symptoms (LUTS), or to advise men about the best treatment options for symptom relief. Because of this, men have to be referred to hospital based urology specialists for tests and diagnosis. 

We aim to establish a practical and accurate decision aid for use by GPs to diagnose the cause of LUTS in men and to assist decisions in determining appropriate person centred treatment. Success of the study will benefit men with LUTS, general practice and the wider health system by:

  • Enabling the use of an innovative and proven GP decision making aid across the NHS
  • Reducing waiting times before men are assessed and diagnosed
  • Giving men early access to appropriate treatment plans personalised to them
  • Reducing the number of men needing referral to hospital based urology specialists
  • Early referral of those men with more complex problems to specialist urology service.

The study will demonstrate if a set of simple test results can be incorporated into a computer software programme for use by GPs to establish a diagnosis of the cause of LUTS in an individual and therefore guide selection of appropriate treatment options to relieve symptoms. With the help of general practices across the UK, we will recruit 880 men with LUTS into the study.

The tests will include men keeping a diary for a few days to record the timing and amount of urine passed, measuring urine flow with a small portable machine, and by asking men to complete symptom questionnaires. To assess the performance and accuracy of the tests, all men in the study will also need to have a more complicated test done by a specially trained nurse.

This special test is called urodynamics and involves the passing of a thin tube into the bladder through which the bladder is then filled with water. Bladder pressure measurements taken during the test show up problems that might be causing the symptoms. A thin rectal catheter is also needed to control for changes in abdominal pressure. By comparing results of the simple tests with results of urodynamics we will identify which simple tests give best agreement.

The top performing simple tests will then be incorporated into development of the decision making aid. The decision aid will be presented to GPs in a format that allows them to enter test results and then get a read out of the diagnosis and recommended treatment. The study will also consider practicalities for both patients and clinical staff in doing the simple tests in the general practice setting, and the ease in which the decision making tool can be used.

Public / patient involvement  

Robert Dixon (The Bladder and Bowel Foundation) acted as our patient and public representative during study development, and was also a co-applicant on the submitted bid. VOICENorth, a public participation group based in the North West of England, were also involved during the study development phase. A panel of male members were recruited to assess feasibility of the invasive erodynamic test that would be a requirement as part of study participation.

The panel members were also involved in the drafting of the lay project summary. One of our co-applicants is the lead for patient and public involvement across Newcastle hospitals, and will be the dedicated PPI coordinator for the study period. She has worked closely with the project team to identify opportunities for patient and public involvement, and to plan these activities in parallel with other study activities.

During the study period, members of the public / patients will be involved in a number of ways. We will be recruiting PPI members from across the 3 study sites (Newcastle, Birmingham, Cardiff), through known groups (e.g. Involving People), and some of these members will be part of the project management team.

The wider group will be consulted on a number of issues, including, but not restricted to, the design of patient facing documents and study recruitment strategies. Patient representatives will also form part of the Consensus Reference Group, which will reach agreement on the best ways to manage lower urinary tract symptoms in men.

How could this research potentially benefit patients? 

Male LUTS is rarely a threat to life or health but patients often find the problem very intrusive to work and social life. The current concentration of diagnostic assessment and initiation of treatment in secondary care usually means a delay in addressing the problem, and inconvenience and extra embarrassment at having to have hospital assessment at a distance from home. A primary care based decision aid with defined accuracy would firstly mean that the men could undergo the necessary simple tests straightaway organised through the GP surgery and secondly would get a much timelier result regarding predicted diagnosis and choice of management options that are most likely to be effective.

For GPs the aid would allay uncertainty around both diagnosis and best management. Specialist urology units could concentrate more on specialist investigation and treating the 10-20% of men who require complex management such as surgery. Those men still requiring early referral or who have not benefitted from simple management options would be referred with a much more informed perspective of their problem with all the initial diagnostics completed making planning of further care quicker and seamless. 

Reducing rates of referral to secondary care for a number of clinical conditions has been identified as one way of improving delivery of NHS care. Full economic evaluation is not included in this study since the design concentrates on diagnostic accuracy as required by the commissioning brief. However, using the rate of consultation and referral documented in the CPRD, we estimate that, if referrals to secondary care were halved, the NHS in England would be saved about £1.3 million per year from reduced out -patient attendance.

Although such a change would require one extra 15-minute consultation with the GP, the relatively low prevalence of the condition means this should not noticeably impact on GP workload. Assessment and initial treatment costs would be unchanged but will be incurred in the primary rather than secondary care setting. Outcome from the patient perspective should not change since GPs will now be receiving the same treatment recommendation from the decision aid that they would have previously been sent from the secondary care urology clinic.

Does the study involve commercial partnership activity?


Does the study involve a methodological innovation?



NIHR Health Technology Assessment (HTA) Programme              

Total grant value


Start date 


End date 


Further info (e.g. related web link)  

Project profile on Centre for Trials Research website:

Follow the PRIMUS project on twitter:

PRIMUS study website:

Outputs generated (Reports / Publications / Impact)

To follow