SPIRIT-Children and Adolescents (SPIRIT-C) 2026 extension statement: enhancing the reporting and usefulness of paediatric randomised trial protocols

Randomised controlled trial (RCT) protocols contain essential details needed to understand and evaluate the trial's planned aims, design, data collection methods, monitoring, data analysis, and participants' safety. However, key information is often omitted from paediatric RCT protocols, including details on dose adjustments of interventions based on age, body surface area, or weight; developmental appropriateness of trial outcome measures and processes; or strategies to minimise participants' anxiety and pain. These deficiencies impair the planning and implementation of potentially impactful trials for children and adolescents. Appropriate guidance is needed to support harmonised, comprehensive reporting of paediatric RCT protocols involving participants aged 0–19 years. The methodological framework for developing reporting guidelines published by the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network was implemented to develop a paediatric extension to the Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) 2025 guidelines, called SPIRIT-Children and Adolescents (SPIRIT-C) 2026. A list of candidate reporting items was generated from the literature, and a Youth Advisory Group and a Family Caregiver Advisory Group contributed essential input throughout the project. An international Delphi study with a priori consensus thresholds, a consensus meeting, group writing of the explanation and elaboration paper, and pilot testing of the draft guideline were conducted. SPIRIT-C 2026 consists of a checklist with 17 new reporting items for reporting paediatric RCT protocols; four items are youth generated and six youth endorsed. SPIRIT-C 2026 can be considered a minimum set of reporting items pertinent to paediatric RCT protocols that are relevant to various interest holders, including young people, family caregivers, researchers, paediatric trialists, ethics committees, regulators, funders, and journal editors. The accompanying explanation and elaboration paper explains all items and offers examples of good reporting. Widespread implementation and uptake of SPIRIT-C 2026 should enhance the quality and usefulness of protocols for RCTs that involve participants from birth through adolescence, and ultimately foster high-quality paediatric trials.