ORIGINAL ARTICLE Year : 2023  |  Volume : 34  |  Issue : 3  |  Page : 142-147

Level of scientific evidence underlying recommendations arising from the functional urology guidelines

Kobra Movalled1, Morteza Zavvar2, Hooman Zafardoust2, Hanieh Salehi-Pourmehr3, Salvador Arlandis4, Amirhossein Ghavidel-Sardsahra5, Sakineh Hajebrahimi6
1 Student Research Committee, Tabriz University of Medical Sciences; Research Center for Evidence-Based Medicine, Iranian EBM Center: A Joanna Briggs Institute Center of Excellence, Tabriz University of Medical Sciences, Tabriz, Iran
2 Student Research Committee, Tabriz University of Medical Sciences, Tabriz, Iran
3 Research Center for Evidence-Based Medicine, Iranian EBM Center: A Joanna Briggs Institute Center of Excellence, Tabriz University of Medical Sciences, Tabriz, Iran
4 Department of Urology, La Fe University and Polytechnic Hospital, Valencia, Spain
5 Tehran University of Medical Sciences, Tehran, Iran
6 Research Center for Evidence-Based Medicine, Iranian EBM Center: A Joanna Briggs Institute Center of Excellence, Tabriz University of Medical Sciences; Urology Department, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran

Date of Submission23-Jul-2022Date of Decision13-Oct-2022Date of Acceptance30-Dec-2022Date of Web Publication12-Jul-2023

Correspondence Address:
Sakineh Hajebrahimi
Research Center for Evidence-Based Medicine, Faculty of Medicine, Tabriz University of Medical Sciences, Azadi Street-Golgasht Ave., Tabriz 5166/15731, East Azarbaijan
Iran

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/UROS.UROS_82_22

Purpose: This study aimed to review the functional urology guidelines, relate the level of evidence (LOE) of their recommendations and highlight the discrepancies between the LOE and grade of recommendation. Materials and Methods: The electronic search was conducted in May 2019 and updated in February 2021. Three researchers separately reviewed the extracted guidelines based on the Appraisal of Guidelines for Research and Evaluation II instrument. We extracted recommendations from each guideline and ranked them into three Grades of A, B, and C; and their evidence into four levels of I to IV. Results: Among the published functional urology guidelines, 18 guidelines were published between 2014 and 2020. Overall, 592 recommendations were abstracted. Of these, 121 recommendations were related to evaluation or diagnosis, and the others (n = 471) on the disease management. These recommendations were in the field of urinary incontinence (UI) (n = 216), overactive bladder (OAB) (n = 172), lower urinary tract symptoms (LUTS) (n = 126), and neurogenic bladder (NGB) (n = 78). Subgroup analysis showed that most of the recommendations in relation to UI were Grade A (n = 111; 51.4%), and one-third were Grade C (n = 83; 38.4%). The remaining 22 recommendations were Grade B (10.2%). In OAB, most of the recommendations were Grade B (n = 67, 39.0%), 55 of them were Grade A (32.0%) and the rest were Grade C (n = 50, 29.1%). Among UI guidelines, 51 (45.9%) Grade A recommendations were supported by LOE I evidence, and 39 (47.0%) Grade C recommendations were supported by LOE IV evidence. Across OAB guidelines, 43 (78.2%) Grade A recommendations were supported by LOE I evidence, and 20 (40.0%) Grade C recommendations were supported by LOE IV evidence. Across LUTS guidelines, 34 (61.8%) Grade A recommendations were supported by LOE I evidence, and 14 (23.3%) Grade C recommendations were supported by LOE IV evidence. Among NGB guidelines, 21 Grade A recommendations were supported by LOE I evidence, and 9 Grade C recommendations were supported by LOE IV evidence. Conclusion: Most of the recommendations in the field of functional urology are not based on the systematic review and meta-analysis of randomized controlled trials (RCTs) and high quality RCTs; which indicates that more attention is still needed in making decisions based on the certainty and grade of recommendations.

Keywords: Functional urology, grade, guidelines, urinary incontinence

How to cite this article:
Movalled K, Zavvar M, Zafardoust H, Salehi-Pourmehr H, Arlandis S, Ghavidel-Sardsahra A, Hajebrahimi S. Level of scientific evidence underlying recommendations arising from the functional urology guidelines. Urol Sci 2023;34:142-7
How to cite this URL:
Movalled K, Zavvar M, Zafardoust H, Salehi-Pourmehr H, Arlandis S, Ghavidel-Sardsahra A, Hajebrahimi S. Level of scientific evidence underlying recommendations arising from the functional urology guidelines. Urol Sci [serial online] 2023 [cited 2023 Sep 29];34:142-7. Available from: https://www.e-urol-sci.com/text.asp?2023/34/3/142/381332   Introduction 

Before the development of evidence-based medicine (EBM) in the 1990s, practitioners used to make clinical decisions based on unsystematic observation and accumulated knowledge.[1],[2] The primary principle of EBM denoted that there is a hierarchy of evidence and different types of evidence vary in strength.[3] Randomized controlled trials (RCTs) and meta-analyses constitute the tip of the hierarchy of evidence because they are the least biased studies, whereas editorials and expert opinions are frequently influenced by clinical judgments and experiences, making them low-level evidence.[4]

Making clinical decisions based on evolving scientific information is a major challenge in medicine. Clinical guidelines have been developed using a combination of the available data to assist clinicians in using the best practice possible. The evidence used in each guideline is assigned the level of its original study's reliability. A number of recommendations are made and a grade is given to them based on the consensus of the guideline panel, which helps in clinical decision-making.[5],[6]

Urologic disorders happen through all stages of life, affecting individuals by impairing their quality of life. The economic burden of urologic diseases is considerable for patients and families, and society on a great scale.[7] Urinary incontinence (UI), neurogenic bladder (NGB), overactive bladder (OAB), and lower urinary tract symptoms (LUTSs) are common urologic complaints that cause a great deal of discomfort and distress to the patients and financial burden to societies.[8] Most studies have found that the prevalence of various UI types ranges from 25% to 45%[9],[10] and that OAB from 10% to 20%. According to a prevalence estimate for LUTS, 45.2% of the population is suffering from this condition.[11] There are few studies that estimated the prevalence of NGB, but available data on its prevalence in various underlying conditions reported 40%–90% in patients with multiple sclerosis, 37%–72% in patients with Parkinson's disease, 15% in patients with stroke, and 70%–84% in patients suffering from spinal cord injury.[12],[13],[14]

Guidelines use different tools to assess the strength of recommendations and the level of evidence (LOE) that supports them. There are discrepancies between how these tools define the grade of recommendation and LOE that cause a great deal of confusion in practitioners referring to several clinical decision-making guidelines.

Using high levels of evidence is substantial for a guideline to be considered worthy of implementation in clinical judgment; hence distinguishing guidelines that have used higher LOEs than others enables the selection of the most reliable ones for best practice. Since there is no systematic review focused on the evaluation of recommendations and their LOE and grade among functional urology guidelines, studies need to meet this purpose.

This study aimed to review the guidelines associated with UI, NGB, OAB, and LUTS, relate the LOE of their recommendations, and highlight the discrepancies between the LOE and the grade of recommendation.

[TAG:2]Materials and Methods[/TAG:2]

Search strategy and selection criteria

The search was conducted in May 2019, and search results were updated in February 2021 in six databases, which include Guidelines International Network, Cochrane Library, Trip database, PubMed, National Institute for Health and Care Excellence, and Agency for Healthcare Research and Quality, using the following keywords and their combination: UI, NGB, OAB, and LUTS and guideline. In addition, we manually searched all guidelines containing the mentioned keywords.

Screening, selection, and quality assessment

Three researchers reviewed the extracted guidelines based on the Appraisal of Guidelines for Research and Evaluation II instrument.[15],[16] The unavailable guidelines, not in English, did not provide LOE or grades for their recommendations, and the ones that did not highlight the LOE, and the grades were excluded. After removing the duplicate, short version, and non-English guidelines, the title, abstract, and full text of the remaining guidelines were reviewed. Consensus was reached in order to address disagreements in the screening and selection of the guidelines [Figure 1]. This process was managed using EndNote X9. Finally, 18 clinical guidelines from 2014 to 2020 were included: 8 UI guidelines, 2 NGB guidelines, 4 OAB guidelines, and 4 LUTS guidelines [Table 1].

Figure 1: Literature flow diagram. LOE: Level of evidence, GOR: Grade of recommendation

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Data extraction

Various tools were used for grading of recommendations and evaluation of evidence implemented by guideline expert panels. This makes it extremely difficult to compare LOE guidelines and grades of recommendation. Hence, we created a tool for grading recommendations and evaluation of evidence that comprises different grading and evaluation systems used in collected guidelines. We relied on each guideline's own method of categorizing evidence rather than independently assessing the level of the evidence supporting each recommendation. Discrepancies were resolved by consensus. We extracted recommendations from each guideline and ranked them in three Grades of A, B, and C [Table 2] and their evidence into four levels: I, II, III, and IV.

LOE I evidence is supported by data from a meta-analysis of RCTs and high-quality RCTs. Data from moderate-quality RCTs support LOE II evidence, well-run controlled nonrandomized trials, a meta-analysis of good-quality cohort studies, well-designed cohort, case control, and quasi-experimental studies. LOE III evidence is supported by data from low-quality RCTs, not-well-designed cohort and case–control studies, correlation, ecological and cross-sectional studies, case reports, and case series, and LOE IV evidence is supported by expert opinion or based on clinical principles.

Data synthesis and analysis

The extracted data were summarized and analyzed in Excel using descriptive statistics, which include mean, standard deviation, frequency, and percentage frequency. The inferential analysis and assessment of the relationship between the variables were carried out in SPSS software (SPSS 21, SPSS Inc., Chicago, IL, USA).

  Results 

Among the published functional urology guidelines, we reviewed 18 guidelines that were published between 2014 and 2020. A total of 592 recommendations were abstracted. Of these, 121 recommendations were related to evaluation or diagnosis, and the others (n = 471) on the disease management. These recommendations were in the field of UI (n = 216), OAB (n = 172), LUTS (n = 126), and NGB (n = 78).

Across these guidelines, 279 recommendations were classified as Grade A, 108 as Grade B, and 205 as Grade C [Table 3].

In addition, 189 (31.9%) recommendations were classified as LOE I, 144 (24.3%) as LOE II, 114 (19.3%) as LOE III, and 145 (24.5%) as LOE IV, and the mean number of recommendations for each guideline was 33.

Among the UI guidelines, 51 (45.9%) Grade A recommendations were supported by LOE I evidence, and 39 (47.0%) Grade C recommendations were supported by LOE IV evidence. Among the OAB guidelines, 43 (78.2%) Grade A recommendations were supported by LOE I evidence, and 20 (40.0%) Grade C recommendations were supported by LOE IV evidence. Among the LUTS guidelines, 34 (61.8%) Grade A recommendations were supported by LOE I evidence, and 14 (23.3%) Grade C recommendations were supported by LOE IV evidence. Among the NGB guidelines, 21 Grade A recommendations were supported by LOE I evidence, and 9 Grade C recommendations were supported by LOE IV evidence.

Subgroup analysis showed that most of the recommendations in relation to UI were Grade A (n = 111; 51.4%), and one-third was Grade C (n = 83; 38.4%). The remaining 22 recommendations were Grade B (10.2%). In OAB, most of the recommendations were Grade B (n = 67; 39.0%), 55 of them were Grade A (32.0%), and the rest were Grade C (n = 50; 29.1%). [Table 4] summarizes the characteristics of recommendations in the field of LUTS and NGB. The Chi-square analysis results showed a statistical difference between grading in various functional urology recommendations (P < 0.001). The frequency of grading and LOE in different fields of functional urology guidelines are illustrated in [Figure 2].

Table 4: Frequency of grading of recommendation in different fields of functional urology

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Figure 2: Frequency of grading and LOE in different fields of functional urology guidelines. LOE: Level of evidence, OAB: Overactive bladder, LUTS: Lower urinary tract symptom, NGB: Neurogenic bladder

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We analyzed the recommendations of these guidelines based on their content, diagnosis, and management [Table 5]. In addition, [Figure 3] illustrates the grade and LOE of recommendations according to the subgroup analysis.

Table 5: Frequency of the diagnosis recommendations or management of the conditions

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Figure 3: Subgroup analysis for recommendations. OAB: Overactive bladder, LUTS: Lower urinary tract symptom, NGB: Neurogenic bladder

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  Discussion 

The goal of the urological clinical practice guidelines is to assemble and summarize the best existing evidence to guide urologists in EBM practice. The recommendations with Grade A and LOE I support are the most reliable for the implying best practice, and guidelines consisting of these kinds of recommendations are more valuable. Our study found that among all the recommendations in four fields of UI, NGB, LUTS, and OAB, 47.13% are Graded A, and about half of which are supported by LOE I and almost one-fifth is supported by LOE IV. It is important to consider that some Grade A recommendations, including history taking and physical examination, are principles of diagnosis or management but are not supported on strong evidence, which are integral parts of a patient's medical evaluation. The OAB guidelines have the most Grade A recommendation that is supported by LOE I (78.18%); on the contrary, the NGB guidelines have the least (36.21%), suggesting that OAB-related recommendations in guidelines are stronger than the other three fields. With regard to the low number of LOE I/Grade A recommendations in the NGB guidelines, we should consider that NGB has a complex population with very different pathologies and, in general, with low numbers of patients. Therefore, it may not be simple to design good-quality RCTs, and it may be more challenging to have high-quality evidence in this area than in other functional urology fields.[33]

We demonstrated that the most common grade of recommendation among the UI and NGB guidelines is A, OAB is B, and LUTS is C; therefore, researchers should focus more on conducting high-quality studies in the field of LUTS.

There are about three times more recommendations about management than diagnosis in all four fields. Overall, Grade A recommendations that are supported by LOE I are more prevalent in the management (62.86%) than in the diagnosis (24.64%). This may indicate the need for stronger evidence in the area of diagnosis. However, there are several challenges in designing high-evidence studies in the field of diagnosis, and there is a lack of sponsored RCTs in this field compared to drug treatment.[35]

To our knowledge, this is the first systematic review that evaluates the levels of evidence and grades of recommendation for any functional urology disorders. The strength of clinical guidelines has been evaluated in studies in several medical specialties. For example, in dermatology, Cook et al.[36] found that only 36.5% of the recommendations were supported by strong evidence. In 2009, Tricoci et al.[37] evaluated the data from the American College of Cardiology/American Heart Association guidelines and found that 11% of the recommendations were supported by strong evidence; in 2019, Fanaroff et al.[38] updated the results indicating 8.5% supported by strong evidence, including about 80% of strong recommendations (consistent with our Grade A). Meyer et al.[39] found that in the American College of Gastroenterology, only 15% of the guidelines were supported by high-level evidence. In obstetrics and gynecology, Wright et al.[40] concluded that only 30% of the recommendations were based on high-quality evidence. Shah et al.[41] found that 0% of the evidence underlying the clinical practice guidelines for venous thromboembolism in the American College of Chest Physicians (CHEST) was supported by the highest-quality ratings, and in 2011, Poonacha and Go[42] found that 9% of the clinical guidelines of the National Comprehensive Cancer Network recommendations were based on high-quality evidence.

The following are some of the advantages of our study: We evaluated the latest editions of all available English clinical guidelines in both common and major functional urology disorders.

Each guideline used a system for grading of recommendations and evaluating the LOE. While some employed the same method, a majority differed in their evaluation system. In order to compare LOE and grade of recommendation among guidelines, we created a new system for classifying evidence and recommendations.

There are also some drawbacks to this study. The LOE supporting each recommendation was not evaluated independently. There might be an inconsistency between the type of study and our definition of LOE. We did not take into consideration the recommendations of each clinical practice guideline. When compared with others, the grading method was different in the EAU guidelines. Even though we assessed each guideline's system for LOE and grade of recommendation, we did not mention their differences in this paper and focused on the discrepancies between LOEs and grades of recommendations.

  Conclusion 

The majority of the recommendations in the field of functional urology are not based on the systematic reviews and meta-analyses of RCT and high-quality RCTs, which indicates that a greater focus is still needed when making decisions based on the certainty and grade of recommendations. Most of the high-quality evidence were focused on the management and treatment of the condition; there were few strong recommendations for diagnosis, prevention, and follow-up. Even though clinical guidelines offer reliable information based on the best available evidence, practitioners should remain attentive to the limitations of guidelines. Discrepancies between definitions of grades of recommendations and LOEs in guidelines necessitate a unanimous tool for classifying grades and LOEs.

Data Availability Statement

Data sharing not applicable to this article as no datasets were generated or analyzed during the current study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 

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  [Figure 1], [Figure 2], [Figure 3]
 
 
  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]