INVESTIGATE-I (INVasive Evaluation before Surgical Treatment of Incontinence Gives Added Therapeutic Effect?): study protocol for a mixed methods study to assess the feasibility of a future randomised controlled trial of the clinical utility of invasive urodynamic testing

Abstract

BackgroundUrinary incontinence is an important health problem to the individual sufferer and to health services. Stress and stress predominant mixed urinary incontinence are increasingly managed by surgery due to advances in surgical techniques. Despite the lack of evidence for its clinical utility, most clinicians undertake invasive urodynamic testing (IUT) to confirm a functional diagnosis of urodynamic stress incontinence before offering surgery for this condition. IUT is expensive, embarrassing and uncomfortable for women and carries a small risk. Recent systematic reviews have confirmed the lack of high quality evidence of effectiveness.The aim of this pilot study is to test the feasibility of a future definitive randomised control trial that would address whether IUT alters treatment decisions and treatment outcome in these women and would test its clinical and cost effectiveness.Methods/designThis is a mixed methods pragmatic multicentre feasibility pilot study with four components:-(a) A multicentre, external pilot randomised trial comparing basic clinical assessment with non-invasive tests and IUT. The outcome measures are rates of recruitment, randomisation and data completion. Data will be used to estimate sample size necessary for the definitive trial.(b) Qualitative interviews of a purposively sampled sub-set of women eligible for the pilot trial will explore willingness to participate, be randomised and their overall trial experience.(c) A national survey of clinicians to determine their views of IUT in this context, the main outcome being their willingness to randomise patients into the definitive trial.(d) Qualitative interviews of a purposively sampled group of these clinicians will explore whether and how they use IUT to inform their decisions.DiscussionThe pilot trial will provide evidence of feasibility and acceptability and therefore inform the decision whether to proceed to the definitive trial. Results will inform the design and conduct of the definitive trial and ensure its effectiveness in achieving its research aim.Trial registration numberCurrent Controlled Trials ISRCTN71327395 assigned 7th June 2010.

Understanding variations in patient screening and recruitment in a multicentre pilot randomised controlled trial: a vignette-based study

“…This confirmed that all employed similar procedures in relation to screening, in adherence with that laid out in the study protocol [5]. It was nonetheless possible that, although procedures were standardised and adhered to, variability in assessment of potential eligibility amongst recruiting staff may have resulted in variations in screening and recruitment.…”

Assessing professional equipoise and views about a future clinical trial of invasive urodynamics prior to surgery for stress urinary incontinence in women: A survey within a mixed methods feasibility study

“…There are several reasons to conduct a pilot trial and feasibility assessment before undertaking a definitive trial of IUT prior to surgery for SUI or stress predominant MUI. These were reviewed in the background to the published protocol for this study 14. The INVESTIGATE‐I study was therefore planned as a mixed methods study looking at the feasibility of a definitive trial of the clinical and cost‐effectiveness of IUT prior to surgery for SUI or stress predominant MUI 15.…”

Urodynamic studies for management of urinary incontinence in children and adults: A short version Cochrane systematic review and meta‐analysis

“…Ninety‐one studies were considered but 83 were excluded because they did not randomize patients to at least one type of urodynamic investigation or one method of performing a urodynamic investigation. One other trial is ongoing …”

“…One new trial among women is in progress and has completed recruitment in January 2013 (attaining 222 participants of a targeted 240) . It is possible, when results are available, that the findings of this trial may produce robust, reliable evidence.…”