Establishing core outcomes and minimal clinically important differences for childhood steroid sensitive nephrotic syndrome clinical trials: results from a Delphi consensus process

Background Few randomized controlled trials are conducted in childhood nephrotic syndrome, and substantial global practice variation exists. Trials have not reported consistent outcomes, patient-reported outcomes, or justified minimal clinically important differences (MCID). Our aim was to establish consensus on core outcomes, assessment timepoints, MCIDs, and desirability of outcome ranking (DOOR) endpoints for future childhood steroid-sensitive nephrotic syndrome research.

We conducted a two-stage Delphi consensus survey of international healthcare providers and Canadian patients and caregivers with experience in childhood nephrotic syndrome. Respondents rated potential outcomes using Likert scales and assigned MCID values for relapse and remission endpoints. Following the surveys, we held workshops for healthcare providers and patients/caregivers in Toronto, Canada, with facilitated discussions. Qualitative data was analyzed thematically to explore perspectives on childhood nephrotic syndrome clinical trial outcomes and MCIDs.

Eighty-one participants (45 providers, 36 patients/caregivers, 63% Canadian) responded to the surveys. Three disease outcomes (relapse rate, relapse-free survival, and relapse occurrence) met consensus criteria as core outcomes. Median MCID values were a 25% absolute difference between two treatments in relapse risk by 1-year (for relapse prevention) choices and 10% absolute difference in remission by 2 weeks (for relapse treatment). Consensus was achieved for five core patient-reported outcomes (pain, physical symptoms, physical function and mobility, life participation, and social function) and DOOR endpoints for nephrotic syndrome relapse and remission.

Consensus exists among surveyed participants on core disease and patient-reported outcomes for childhood nephrotic syndrome research. Findings can improve the quality and reporting of future trials in this population. Graphical Abstract Similar content being viewed by others Data availability Deidentified individual participant data will not be made available.

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We thank the survey and workshop participants and volunteer staff for their time and effort as well as the nurses and staff from the Nephrology Clinic at The Hospital for Sick Children. Funding Dr. Cal Robinson received salary support from the Cure Glomerulopathy consortium Career Development Fellowship program, the SickKids Clinician-Scientist Training Program, the Canadian Institutes of Health Research Fellowship program, and the Kidney Foundation of Canada KRESCENT Program. Dr. Rulan Parekh was supported by the Women’s College Hospital Research Institute F.M. Hill Chair in Health System Solutions. Dr. Parekh also reports consultant fees from Vertex and Sanofi unrelated to this manuscript. Dr. Eddy Fan reports personal fees from ALung Technolodies, Baxter, Getinge, Inspira, Vasomune, and Zoll Medical unrelated to this manuscript. The other authors have no relevant funding to declare. Author information Authors and Affiliations Contributions C. H. R., R. S. P., and A. H. designed the study; S. Ca., B. C., E. F., and J. V. R. critically appraised and revised the study protocol and initiation documents; C. H. R., N. A., S. Ch., M. G., V. R., J. V. R., and R. S. P. planned and led the provider and patient workshops, C. H. R. was responsible for all statistical analysis; C. H. R. produced the tables and figures; C. H. R. drafted the manuscript; all authors revised the manuscript and approved the final version of the manuscript prior to submission. Corresponding author Ethics declarations Competing interests The authors declare no competing interests. Additional information Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary Information Below is the link to the electronic supplementary material. Rights and permissions Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law. About this article Cite this article Robinson, C.H., Carter, S., Aman, N. et al. Establishing core outcomes and minimal clinically important differences for childhood steroid sensitive nephrotic syndrome clinical trials: results from a Delphi consensus process. Pediatr Nephrol 41, 399–411 (2026). https://doi.org/10.1007/s00467-025-06960-6 Received: Revised: Accepted: Published: Version of record: Issue date: DOI: https://doi.org/10.1007/s00467-025-06960-6