Regarding guideline development, we will follow the new guideline definition from the IOM , comply with the World Health Organization handbook for guideline and follow the Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool to form recommendations . In addition, we will closely adhere to the six domains of the AGREE II  and the Reporting Items for Practice Guidelines in Healthcare (RIGHT) working group . We have registered the CPG on the International Practice Guidelines Registry Platform (http://www.guidelines-registry.cn/user/guid/tail/1276), and the registration number is IPGRP-2021CN305. The need for ethics approval was waived by the Institutional Review Boards of the XX University.
2.2 Participating institutions
The CPG started in May 2021 and was launched by Evidence-based Nursing and Midwifery Practice Center, Southern Medical University, and Evidence-based Medicine Center, Lanzhou University, which will be titled, ‘Prevention and Management of Perineal Tears at Vaginal Delivery: An Evidence-based Clinical Practice Guideline’.
2.3 Guideline working group
The Guideline working Group, consisting of a Guideline Steering Group, a Guideline Development Group, a Systematic Evaluation Group, a Guideline Secretary Group and an External Review Group, has been established in May 2021.
The Guideline Steering Group has been composed of 2 clinical medical experts, 2 midwifery experts and 1 nursing expert. This group will be in charge of the following mission: (1) identifying and approving members of the other four groups and collecting all member’s statements of interest conflicts, (2) supervising the whole process such as authorizing the CPG’s scope, supervising literature search and systematic reviews, examining the quality of evidence, developing the final recommendations based on the revised Delphi approach and ratifying the release of the CPG, (3) responding to the end-user’s feedback, (4) tracking new evidence and deciding whether the CPG needs to be updated.
To ensure fair representation by gender and region, the Guideline Development Group has consisted of 22 members from multiple fields of specialization. There are 2 obstetric experts, 7 midwifery experts, 9 nursing managers (with rich obstetric working experience), 1 nursing educator and 3 evidence-based medical experts. The 22 members come from14 provinces, 2 municipalities, and 1 autonomous region in China, covering China’s northeast, northwest, north, southwest, south, and other regions. The Guideline Development Group will be in charge of the following mission: (1) developing the scope of the guideline, drafting the Population, Intervention, Comparison, Outcomes (PICOs), (2) prioritizing the critical outcomes, (3) formulating the recommendations after considering the overall balance of benefits and harms under Chinese Context, (4) dealing with the opinions from the External Review Group, (5) approving the final CPG, (6) publishing and promoting the CPG.
The Systematic Evaluation Group has been composed of 11 members with the experience of producing systematic reviews, whose primary responsibilities are: (1) conducting evidence retrieval and synthesis for each recommendation, (2) critically assessing the quality of the evidence, (3) making the summary of findings tables (SoFs tables), (4) drafting the initial recommendations.
The External Review Group has been composed of 1 obstetrician, 4 midwifery experts and 1 methodological expert, mainly responsible for reviewing the recommendations and the final guideline document.
The Guideline Secretary Group has been composed of 3 members, whose primary responsibilities are: (1) assisting the guideline steering group in the development of the guidelines, (2) collecting initial clinical questions, (3) surveying patients’ views and favors, (4) recording the details of the whole process, and (5) drafting and finalizing the CPG.
2.4 Guidelinetarget users and population
The target users of the CPG include obstetricians, gynecologists, midwives, nursing staff, journal editors as well as relevant researchers. The target population include pregnant women who intend to have vaginal delivery or being undergoing vaginal delivery and women with perineal tears during vaginal delivery.
2.5 Declaration of Interests and Funding Support
All individuals engaged in the Guideline Working Group were required to complete declaration of interest forms to enhance the transparency and credibility of the CPG. The CPG has been supported by XX University.
2.6 Formulating clinical questions and choosing outcomes
A theoretical analysis of existing evidence on perineal tears prevention and management plus surveys with target users and population, have been used to determine the initial list of clinical questions. These questions have been sent to the Guideline Development Group for review, revision, and supplementation via Delphi surveys. The identified clinical questions have then be structured in PICO format. Furthermore, the outcomes have been rated in order of importance by the Guideline Development Group through online surveys. Panelists have been asked to score each outcome from 1 to 9 (7–9 indicate critical for a decision, 4–6 indicate important, and 1–3 indicate not important) based on the effectiveness and safety of the interventions. Then the PICOs of the CPG and the outcomes have been finalized by the Guideline Steering Group. This CPG has covered 21 clinical questions and these clinical questions can be grouped into two categories: (1) What are the effective and safety interventions to prevent perineal tears at vaginal delivery, (2) What are the effective and safety interventions to manage perineal tears.
2.7 Evidence Retrieval and Synthesis
The following electronic databases have been systematically searched for eligible studies in PubMed, Embase, the Cochrane Library, CINAHL and three Chinese literature databases (CBM, CNKI and WanFang). The search deadline was August in 2021. Our search terms were a combination of text free terms and Medical Subject Headings (MeSH) terms. The search strategy has been appropriately adjusted according to the specific PICO questions and the characteristics of each database. The reference lists of the included literature have been scrutinized to identify additional relevant studies.
Endnote X9 software has used to screen and manage the literature. Randomized controlled trials (RCTs) related to the study have been retrieved for each PICO question and based on review of the titles, abstracts, and full texts. To ensure the consistency of the literature selection standards, all members of the Systematic Evaluation Group conducted a pre-test. We randomly selected 20 references for the pre-test. By summarizing the results of our literature selection and discussing the inconsistencies, all members had a definite understanding of the inclusion and exclusion criteria.
In order to incorporate China’s domestic literature, a systematic review will be undertaken by the Systematic Evaluation Group for each of the PICO questions following the Cochrane Handbook version 5.1.0. The risk of bias of the included studies will be assessed by two independent reviewers using the Cochrane Collaboration tool (risk of bias, ROB) for assessing randomized controlled trials. The data of the included studies have then been extracted by the two researchers independently using a standardized data extraction form, which has been cross-checked by two reviewers. A senior reviewer will be asked to resolve any disagreements through a group discussion. If the extracted data show effect homogeneity across studies, then these data can be combined using meta-analyses. Conversely, if heterogeneity exists, the evidence will be presented in a narrative synthesis. The systematic review will be presented in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement.
2.8 Evaluating evidence and developing recommendation strength
The guideline methodologists will be in charge of training all members of Systematic Evaluation Group to evaluate the evidence quality. The GRADE system will be adopted by the Systematic Evaluation Group to rate the quality of the body of evidence as high, moderate, low or very low. The GRADE evidence profiles  and the SoFs tables for each PICO question will be prepared and presented to the guideline development group. The group will discuss the quality of the evidence, the patients’ values and preferences, the balance between the pros and cons, the economic analysis and the impact of resources according to the GRADE tool. The strength of recommendations will be preliminarily determined through 2–4 rounds of the Delphi process by using GRADE grid . The strength of recommendation is divided into strong recommendation, weak recommendation, unclear recommendation, weak no recommendation, strong no recommendation. The recommendation will be adopted on each item if the approval ratio of the experts is more than 50% for any option or more than 70% for one of the two options on same side. Otherwise, the item will be deemed controversial and will need one more round of the Delphi process. The draft recommendations will be sent to the External Review Group for peer review, then be submitted to Guideline Steering Group for final approval.
2.9 Drafting the guideline
The CPG will be drafted according to the RIGHT statement . The Guideline Secretary Group and the Guideline Steering Group will draft the CPG collaboratively.
2.10 Peer Review of Guideline
The draft CPG will be peer reviewed by external experts. The Guideline Secretary Group will record the review process and the Guideline Development Group will respond to the comments after a full discussion of these comments. The draft CPG can be appropriately revised if necessary.
2.11 Release and update of the guideline
It is estimated that the full text will be published in 2022. This CPG will be translated into English and published in relevant journals. The Guideline Development Group will update the guidelines 3–5 years, with the consideration of specific conditions such as emergence of new relevant evidence after the publication of the CPG and evidence changes affecting the CPG recommendations or changes in the strength of the CPG recommendations.
2.12 Promotion, implementation, and evaluation of the guideline
After releasing the CPG, the dissemination and promotion of the CPG will be implemented by School of Nursing, Southern Medical University. It will be in charge of the following tasks: (1) proposing the CPG in relevant seminars and forums, (2) organizing a learning session or conference to release the CPG to obstetricians, midwives, nursing staff and other related personnel, (3) writing articles related to the CPG and publishing them in journals, popular medical or official health websites, (4) conducting a research to evaluate the impact of the CPG in China and assessing the implementation of the CPG in 2 years after its publication.
2.13 Patient and Public Involvement statement
Women of childbearing age only shall be involved in our study as patient representatives. They will participate in our survey to formulate the clinical questions and choose outcomes.