Design
This systematic review protocol was developed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols 2015 statement (PRISMA-P) of the Enhancing the Quality and Transparency Of health Research (EQUATOR-network), as the Prisma-P Table below at (Additional file 1) (PRISMA-P) [22–24], will be reported in accordance with the PRISMA statement [25] and registered on the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42022301522).
To contemplate the aim of this study will be performed a systematic review following the Cochrane methodology of randomized controlled trials [26].
Eligibility criteria
For this study the eligibility criteria will be according to the model by the Population, Intervention, Comparison, Outcome (PICO) [27].
Types of studies
Primary quantitative research studies published in English or Spanish with no date restriction will be considered. There was and there is an increase in the production of scientific evidence about OAB and improvement of its symptoms. In this study will be included RCTs with adults over 18 years old with OAB, with or without urgency urinary incontinence, receiving any kind of BT intervention with or without supervision, to prevent and/or reduce the OAB symptoms.
Population
The population of interest is women and men, aged 18 years or over with OAB-wet or OAB-dry symptoms.
Intervention
BT will be the intervention of interest. BT consists of a set of techniques that help individuals to delay voiding through activities that require mental concentration, such as relaxation or distraction techniques, often associated with repeated contractions of pelvic floor muscles (PFM), which provide an inhibitory reflex of the detrusor (Urethrosphincteric guarding reflex). Usually a health professional (usually a physiotherapist) teaches and guides the patient to perform bladder training during moments of urgency urinary.
Comparator
Will be used like a comparator group, another intervention or a non-exposed control/placebo group.
Outcome
The primary outcome will be the improvement of OAB symptoms (urinary urgency with daytime voiding frequency, nocturia with or without urgency urinary incontinence), which can be assessed by tools such as urodynamic study, voiding diary, and questionnaires and others instruments that make it possible to assess quantitatively.
The secondary outcome will be the quality of life, functional assessment and adverse events, which can be assessed by questionnaires and measurement instruments.
Exclusion criteria
For this protocol will be excluded all studies that may show design the case studies, cross-over studies, non-comparative study, non-controlled studies, observational cohort, case-control, cohort, cross-sectional and single group observational studies, abstract, opinion piece, integrative mixed methods and systematic reviews, grey literature studies, studies that do not have the separation of the groups nor details of the adequate protocol, or studies that do not present bladder training alone as an endpoint will be given the primary aim of the review is to assess BT in adults with OAB-wet or dry.
Regarding the intervention, studies demonstrating an online orientation, treatment, previous demonstration and orientation about bladder training or having already been previously treated or with urinary tract infection, detrusor overactivity or any other lower urinary tract pathology, bladder or urethral abnormalities, pre, peri and immediate post-operative, uncontrolled metabolic disorders, children, women during pregnancy and puerperium, will be excluded. Similarly, RCTs published that are not shown in English will be excluded.
Information sources and search strategy
Systematic review protocol will be carried out by following the Cochrane methodology of Randomized Controlled Trials. Databases to be searched with no date restriction and no language restrictions, include PubMed Central (PMC)/MEDLINE, Physiotherapy Evidence Database (PEDro), Scientific Electronic Library Online (SciELO), Latin American and Caribbean Literature in Health Sciences (LILACS), Central Cochrane Library, Web of Science, Excerpta Medica database (EMBASE), Cummulative Index to Nursing and Allied Health Literature (CINAHL), and by handing searching to identify studies involving the above-mentioned interventions. MeSH terms and search descriptors that will be used for our searches are “Bladder Training”, “Bladder Drill”, “Bladder Re-education”, “Bladder Retraining”, “Bladder Discipline”, “Overactive Bladder”, “Bladder, Overactive”, “Overactive Urinary Bladder”, “Urinary Bladder”, “Overactive, Urinary Bladder”, “Bladder, Urinary”, “Urinary Bladder Disease”, “Bladder Disease”, “Bladder Detrusor Muscle”, “Detrusor Muscle, Bladder”, “Randomized Controlled trial”, “controlled clinical trial”, “Randomly” and “RCT”, as shown in Table 1.
Table 1
Mesh headings and Searches terms |
1 | Bladder Training |
2 | Bladder Drill |
3 | Bladder Re-education |
4 | Bladder Retraining |
5 | Bladder Discipline |
6 | 1 OR 2 OR 3 OR 4 OR 5 |
7 | Overactive Bladder |
8 | Bladder, Overactive |
9 | Overactive Urinary Bladder |
10 | MH “Urinary Bladder” |
11 | Overactive, Urinary Bladder |
12 | Bladder, Urinary |
13 | MH “Urinary Bladder Disease” |
14 | Bladder Disease |
15 | Bladder Detrusor Muscle |
16 | Detrusor Muscle, Bladder |
17 | 7 OR 8 OR 9 OR 10 OR 11 OR 12 OR 13 OR 14 OR 15 OR 16 |
18 | MH “Randomized Controlled Trial” |
19 | MH “Controlled Clinical Trial” |
20 | Randomly |
21 | RCT |
22 | 6 AND 17 AND 18 AND 19 AND 20 AND 21 |
The Table shown how the search will be conducted, this model will be conducted at model PUBMED base. |
This search will be conducted by AKLR with the assistance of a librarian from the institution. Each term will be combined with the term of the intervention (bladder training, its variations and other terms), combined with the term of the health condition studied (overactive bladder) combined then with the term referring to the type and design of study that will be chosen for the analysis. Primary search terms include ‘bladder training’, 'overactive bladder', ‘urinary incontinence’ and 'urinary urgency incontinence', with common Boolean operators and symbols as illustrated in Table 2. These terms will be searched using MeSH or search descriptors with appropriate changes for each database.
Table 2
Concept 1 | Concept 2 | Concept 3 |
Bladder Training | Overactive Bladder | MH “Randomized Controlled Trial” |
OR | OR | OR |
Bladder Drill | Bladder, Overactive | MH “Controlled Clinical Trial” |
OR | OR | OR |
Bladder Re-education | Overactive Urinary Bladder | Randomly |
OR | OR | OR |
Bladder Retraining | MH “Urinary Bladder” | RCT |
OR | OR | |
Bladder Discipline | Overactive, Urinary Bladder | |
| OR | |
| Bladder, Urinary | |
| OR | |
| MH “Urinary Bladder Disease” | |
| OR | |
| Bladder Disease | |
| OR | |
| Bladder Disease | |
| OR | |
| Bladder Detrusor Muscle | |
| OR | |
| Detrusor Muscle, Bladder | |
Each concept will be combined with “AND”. |
Data management, selection and screening
Database search results will be imported into the reference management software Mendeley Reference Management 2.67.0. Mendeley is the program or software that supports collaborative title and abstract screening, full-text, screening [28]. In this study, for each search strategy, two reviewers will evaluate the studies gathered from the databases in the order: title, abstract and full reading. All studies potentially eligible for inclusion in the review will be selected for full reading. In case of disagreement, a third reviewer will be consulted. Therefore, after the screening outcomes will be saved, documented and shown in a flow diagram recommended by PRISMA Statement [25].
Data extraction
Data extraction for eligible studies will be performed by two reviewers (AKLR e DPVS) who will extract data from articles that meet the inclusion criteria. A standardized form will be used to extract the following information: study characteristics (design, randomization method, blinding, allocation generation and concealment, statistics), which will be assessed for risk of bias and quality of evidence, and in relation to the profile of the participants and the variables that will be extracted as shown in Table 3.
Table 3
Characteristics of the Studies
Title / Author/ year (country) | Number of participants per group | Outcome measure and OAB Symptoms | Primary Outcomes | Interventions in each group (protocols) | Follow-up (Simplified) | Results | Grade Score |
This table represents the study characteristics related to the setting; the number of participants according to group; intervention in each group, outcome measures; and follow-up, results and scores. |
OAB: Overactive bladder |
Studies that do not meet the inclusion criteria will be excluded and added in Table 4 with the reason.
Table 4
Exclusion criteria from systematic review and meta-analysis of randomized controlled trials
First Author, Year of publication | Title | Reasons for exclusion |
Exclusion Table for the systematic review and meta-analysis of randomized controlled trials to evaluated the effects of BT in individuals with OAB-wet or OAB-dry. |
Data items
Will be included from the selected studies the title, author, year, country, study setting, design element, aim, number of participants per group, inclusion and exclusion criteria, type and unit of allocation, start and end dates of the study, duration, baseline group differences, follow-up, satisfaction with treatment, improvement of symptoms, outcome measure and OAB symptoms, others outcomes of self-reported that allow measures and data to be drawn up for comparison as a comparator group and interventions to compare with bladder training, as shown in Table 3.
Outcomes and prioritisation
The outcome that will be prioritised is the effect of BT in the improvement of OAB symptoms. Outcomes will be compared between the groups who do and do not participate in a BT intervention. The Secondary outcomes will be quality of life, functional assessment and adverse events, which can be assessed by questionnaires and measurement instruments. If any discrepancy data is observed, an email will be sent to the authors of the studies to be analyzed.
Risk of bias in individual studies
In this study the methodological quality the risk of bias will be measure by the Cochrane Handbook of Interventions Systematic Reviews, which assesses the following domains: allocation generation; concealment of allocation; blinding (of participants and researchers) and blinding of outcome assessment; the presence of incomplete data; reporting bias of information and other types of bias. The results to these domains may be “High”, “Low” or “Uncertain”. The final grade of the study will be based on the responses given to the first three domains and will be classified as having high, low or uncertain risk of bias. In case of doubt or a tie between the ability of the two reviewers to give an opinion on the individual risk of bias of each study, a third evaluator will be inserted for further information. If there is any doubt as to whether the study did or did not comply with the risk of bias it will be stated that the author did not make it clear and therefore the authors of this study will contact the authors of the study in question for further information on the methodology and datas. The RoB 2, will be used for specific outcomes assessed for the risk of biased domains, including signaling issues that may influence a risk of biased judgments and may lead to an overall biased and unreliable risk judgment [29].
Quality appraisal
In this stage, two authors (AKLR and DV) will check and evaluate each of the articles by using the Mixed Methods Appraisal Tool (MMAT) [30]. Therefore, this method verifies the studies regarding their methodology, however, there will not be a score to verify the quality of each study, thus, an analysis will be used to complete the quality of the studies regarding their outcomes and methodologies [30].
Data synthesis
For between-study analyses, the odds ratio, mean differences or the standardised mean difference will be calculated. In case of missing data, we will try to contact the primary authors to obtain relevant information. We will provide summaries of intervention effects, calculating odds ratio for dichotomous outcomes (with 95% confidence interval), for continuous outcomes, the mean differences or the standardised mean difference, when outcomes are measured using scales not compatible (with 95% CI). Therefore, if possible, due to the range of different outcomes measured across the small number of existing trials, will conduct a meta-analysis. However, if it is possible to have a study with the same type of intervention, a comparator, and the same outcome measure, we can reproduce a random-effects meta-analysis with standardized mean differences outcomes and risk ratios for binary outcomes. Ninety-five percent (95%) confidence intervals and two-sided p-values for each outcome. Review Manager software (RevMan) will be used for all analyses, including meta-analysis with more of two studies will be illustrated using forest plots [26, 31].
To verify the heterogeneity between studies, the effect measures will be evaluated using both the χ2 test and the I² statistic [32]. Therefore, will be considered a value of I² greater than 50% to indicate satisfactory heterogeneity. Low heterogeneity will be considered between 0 and 40%, moderate heterogeneity between 30 and 60%, heterogeneity between 50 and 90% and significant heterogeneity between 75 and 100% [33]. An analysis will be carried out to verify the sub-groups Stratified meta-analyses will be used to assess estimates of heterogeneity according to: study quality, populations studied, logistics of intervention, and content of the intervention.
Meta-bias
The selection of studies for this systematic review protocol will be driven by the PICO model and the full step by step of this protocol. Hand searching will be used to reduce the possibility of publication bias [34, 36]. Therefore, the protocol has been registered to provide transparency and that it can be replicable and intelligible. In this sense, two reviewers will be selected to assess the quality of the studies of low quality studies and will be excluded if they may interfere with the results [22].
Confidence in cumulative evidence
The overall effectiveness and the improvement in individuals with OAB symptoms will be assessed by The Grading of Recommendations Assessment, Development and Evaluation (GRADE) that will verify the quality of evidence of the analyzed studies [35]. To assess the quality of evidence, two authors will evaluate each outcome measure through discussion and consensus. If the data for meta-analysis will be pooled and a narrative analysis performed, the GRADE criteria will be used to evaluate each analytical grouping. The GRADE system assesses the limitations of the study, inconsistencies, indirect evidence, inaccuracies, and publication biases, classifying the level of evidence of the reviewed studies as high, moderate, low, or very low [23, 36, 37].