Supplementary Material for: European Society for Paediatric Endocrinology (ESPE) and European Society of Endocrinology (ESE) Joint Clinical Practice Guidance for Healthcare Transition from Paediatric to Adult Endocrine Care

Background: The transition from paediatric to adult healthcare is a critical period for young individuals with endocrine conditions. Despite numerous published recommendations, Europe still lacks recent, comprehensive, evidence-based, and practically applicable guidelines for endocrine healthcare transition. Objective: To develop European consensus guidance for transition from paediatric to adult care in endocrine conditions through a structured, evidence-based approach. Methods: A systematic literature review identified 351 recommendations from 55 articles (2011-2023). Articles were included if they provided recommendations on transition from paediatric to adult care for patients with endocrine diseases or general (non-disease-specific) transition guidance. The guidance was developed by a core multidisciplinary group (n=7) and refined through focus groups with 18 experts from 10 European countries, representing both paediatric and adult care settings. Patient representatives have reviewed and approved it. Results: The guidance includes recommendations across 11 domains: structure of transition service, patient empowerment, patient-professional relationship, multidisciplinary team organisation, healthcare provider education, timing and planning, care coordination, management of non-attendance, psychological support, parents/caregivers role and readiness tools. Each recommendation was rated as either 'recommend' (strong) or 'suggest' (conditional) based on expert consensus and available evidence. Conclusion: This ESE-ESPE guidance provides a comprehensive, practical framework for endocrine healthcare transition, applicable across different European healthcare settings. The recommendations emphasise structured programs, care coordination, and patient-centred approaches to optimise transition outcomes.