Systematic review and evaluation of methods of assessing urinary incontinence

Citation

(2006), "Systematic review and evaluation of methods of assessing urinary incontinence", Clinical Governance: An International Journal, Vol. 11 No. 4. https://doi.org/10.1108/cgij.2006.24811dae.002

Systematic review and evaluation of methods of assessing urinary incontinence

Systematic review and evaluation of methods of assessing urinary incontinenceJ.L. Martin, K.S. Williams, K.R. Abrams, D.A. Turner, A.J. Sutton, C. Chapple, R.P. Assassa, C. Shaw and F. Cheater,

Background

Although urinary incontinence is not life threatening, it can have enormous costs to individuals and the health service in terms of expenditure and impact on quality of life. Epidemiological studies have demonstrated that urinary incontinence is a very common symptom, with a reported prevalence of any urinary incontinence (in those aged 40 and over) of 34 per cent for women and 14 per cent for men.

Pathways to diagnostic assessment are inconsistent, with some individuals being assessed and treated in primary care settings by GPs and nurses, and others being referred directly to a variety of specialists in secondary care (e.g. physiotherapists, gynaecologists and urologists) without any assessment or treatment. Assessment can be undertaken at a number of levels using different combinations of tests.

It is particularly important when implementing certain treatment interventions (e.g. medication that may have side-effects) that a diagnosis is made to determine the most effective treatment intervention, and it is imperative before surgical intervention. If a diagnosis is not made, then inappropriate and unnecessary interventions may be implemented. Two types of diagnosis can be made: symptomatic diagnosis and condition-specific diagnosis. In general, symptomatic diagnoses are made in primary care using clinical history-taking, urinary diaries, pad tests and validated symptom scales. Condition-specific diagnoses are made in secondary care using urodynamic techniques. The use of diagnostic assessment methods is influenced by the clinical setting and the expertise of the individual undertaking the assessment. The evidence available on the accuracy and acceptability of these diagnostic processes is inconsistent and variable.

Objectives

This systematic review aimed to:

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  identify, appraise and summarise the published evidence relating to different methods of diagnostic assessment of male and female urinary incontinence: specifically urodynamic stress incontinence (USI) and detrusor overactivity (DO);

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  quantitatively synthesise the extracted evidence using meta-analysis methods (where possible) or pooling of individual sensitivity and specificity data;

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  construct an economic model to examine the cost-effectiveness of simple, commonly used primary care tests;

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  identify gaps in the literature; and

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  prioritise future clinical and research questions.

Methods

Data sources. The online bibliographic databases MEDLINE (1966-2002), CINAHL (1982-2002) and EMBASE (1980-2002) were used to obtain the literature. The search strategy was based on the Cochrane and NHS Centre for Reviews and Dissemination strategies for identifying studies of diagnostic performance.

Study selection

Study selection comprised a three-stage process using defined inclusion and exclusion criteria. All records were assessed for relevance by the first investigator on the basis of the abstract, or if the abstract was not available then title only. Papers were considered relevant to the systematic review if they considered the evaluation, appropriateness and/or cost of diagnostic assessment in the following categories:

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  clinical history-taking;

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  simple investigations including validated scales, diaries and pad tests; and

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  advanced (invasive) investigations (e.g. urodynamics).

To be included, a paper had to provide a quantitative comparison between two or more different methods of diagnosing urinary incontinence.

Data extraction

A panel consisting of at least three members of the review team, including at least one statistician, discussed all papers identified as of potential relevance. The panel determined whether study data were presented in a suitable format to calculate sensitivity and specificity.

Quality assessment

All relevant papers were assessed for quality using Quality Assessment of Diagnostic Studies (QUADAS), a tool designed specifically for studies on diagnostic accuracy. An initial pilot study on four papers resulted in a number of clarifications being added to the instructions of the QUADAS tool to ensure consistency between assessors. Seven of the authors performed the full quality assessment process, with 10 per cent of the papers being assessed by two authors to test for inter-reader agreement.

Data synthesis

Studies that reported the results of applying the same diagnostic procedure using the same threshold value (cut-off) were pooled using a random effects meta-analysis model to produce pooled estimates of sensitivity, specificity and diagnostic odds ratio together with 95 per cent confidence intervals.

Results

In total, 6009 papers were identified from the literature search, of which 129 were deemed relevant for inclusion in the review, and these papers compared two or more diagnostic techniques. The gold-standard diagnostic test for urinary incontinence with which each reference test was compared was multichannel urodynamics.

In general, reporting in the primary studies was poor; there was a lack of literature in the key clinical areas and minimal literature dealing with diagnosis in men. Only a limited number of studies could be combined or synthesised, providing the following results when compared with multichannel urodynamics. A clinical history for diagnosing USI in women was found to have a sensitivity of 0.92 and specificity of 0.56 and for DO a sensitivity of 0.61 and specificity of 0.87. For validated scales, question 3 of the Urogenital Distress Inventory was found to have a sensitivity of 0.88 and specificity of 0.60. Seven studies compared a pad test with multichannel urodynamics; however, four different pad tests were studied and therefore it was difficult to draw any conclusions about diagnostic accuracy. Of the four studies comparing urinary diary with multichannel urodynamics, only one presented data in a format that allowed sensitivity and specificity to be calculated. Their reported values of 0.88 and 0.83 suggest that a urinary diary may be effective in the diagnosis of DO in women. Examination of the incremental cost-effectiveness of three primary care tests used in addition to history found that the diary had the lowest cost-effectiveness ratio of between £35 and £77 per extra unit of effectiveness (or case diagnosed). Imaging by ultrasound to determine leakage was found to be effective in the diagnosis of USI in women, with a sensitivity of 0.94 and specificity of 0.83.

Conclusions

This is the first systematic review of methods for diagnosing urinary incontinence. As reporting of the primary studies was poor, clinical interpretation was often difficult because few studies could be synthesised and conclusions made. The following information could be deduced from the available data:

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  A large proportion of women with USI can be correctly diagnosed in primary care from clinical history alone.

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  On the basis of diagnosis the diary appears to be the most cost-effective of the three primary care tests (diary, pad test and validated scales) used in addition to clinical history.

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  Ultrasound imaging may offer a valuable alternative to urodynamic investigation.

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  The clinical stress test is effective in the diagnosis of USI. Adaptation of such a test so that it could be performed in primary care with a naturally filled bladder may prove clinically useful.

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  If a patient is to undergo an invasive urodynamic procedure, multichannel urodynamics is likely to give the most accurate result in a secondary care setting.

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  There is a dearth of literature on the diagnosis of urinary incontinence in men, with no studies meeting the study criteria for data extraction in the diagnosis of bladder outlet obstruction.

Implications for healthcare

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  There is currently a lack of high-quality research in clinically relevant areas to inform clinical practice.

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  Most diagnostic methods can be undertaken in primary or secondary care.

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  Simple investigations (e.g. pad test and diary) may offer useful information on severity which, when combined with history, may provide sufficient information to commence primary care interventions (which are low cost and low risk).

Recommendations for research

Given the demographics of the UK population and the reported high prevalence of any urinary incontinence in the community-dwelling population, there will be an increasing burden placed on primary (and secondary) care services in terms of the diagnostic assessment and appropriate treatment of incontinence. Therefore, identifying which are the most clinically accurate and cost-effective diagnostic methods is of crucial importance.

There is a need for large-scale, high-quality primary studies evaluating the use of a number of diagnostic methods in a primary care setting to be undertaken so that the results of this systematic review can be verified or not. Such studies should include not only an assessment of clinical effectiveness, in this case diagnostic accuracy, but also an assessment of costs and quality of life/satisfaction to inform future health policy decisions.

Studies carried out should be reported to a better standard. The recommendations of the Standards for Reporting of Diagnostic Accuracy (STARD) initiative should be followed to ensure the accuracy and completeness of reporting design and results.

©2006 Crown Copyright

(J.L. Martin, K.S. Williams, K.R. Abrams, D.A. Turner and A.J. Sutton are based at the Department of Health Sciences, University of Leicester, UK. C. Chapple is based at the Urology Research, Royal Hallamshire Hospital, Sheffield, UK, R.P. Assassa is based at Pinderfields and Pontefract General Infirmary, UK. C. Shaw is based at the Department of General Practice, University of Wales, College of Medicine, UK. F. Cheater is based at the School of Healthcare Studies, University of Leeds, UK.)