Quality appraisal of clinical practice guidelines for fertility preservation in patients with breast cancer: a systematic review using AGREE II and AGREE-REX

ObjectiveThis review utilizes the AGREE II instrument to evaluate the methodological rigor and the AGREE-REX instrument to evaluate the implementability of recommendations within clinical practice guidelines for fertility preservation in patients with breast cancer. This is the first study to comprehensively appraise related guidelines using both officially recognized instruments. The findings aim to inform clinical application by identifying high-quality and implementable guidelines.MethodsBy June 2026, a systematic search was conducted across seven electronic databases, six guideline repositories, and relevant breast cancer society websites. Guidelines were screened according to predefined criteria, and independent quality assessments were performed using AGREE II and AGREE-REX. Inter-rater reliability was evaluated via the intraclass correlation coefficient (ICC).ResultsTwelve guidelines were included. The AGREE II domain scores (mean standardized percentages) showed significant variations: Scope and Purpose (72.98%), Editorial Independence (71.81%), Clarity of Presentation (70.05%), Applicability (69.33%), Rigor of Development (55.30%), and Stakeholder Involvement (54.78%), highlighting critical gaps in patient participation and evidence updating mechanisms. Based on AGREE II and AGREE-REX evaluations, five guidelines were classified as Grade A (strongly recommended), four as Grade B, and three as Grade C.ConclusionThe five Grade A guidelines predominantly originated from Western countries. Prior to clinical implementation, they require cultural adaptation, language translation, and local validation to align with regional healthcare systems and patient values. Future guideline development should prioritize stakeholder integration, dynamic updating mechanisms, and resource allocation assessments to enhance clinical applicability.Systematic Review Registrationhttps://www.crd.york.ac.uk/PROSPERO/, PROSPERO CRD42023464394.