A novel US-based grading system for disease severity in sickle cell disease: the Sickle Cell Outcome Grading System...

Sickle cell disease is a haematological disorder marked by recurrent events and progressive organ dysfunction, yet a standardised framework to assess disease severity is lacking. We developed a novel US-based severity grading system through identification of sickle cell disease-related complications mapping all to the Common Terminology Criteria For Adverse Events and applying a five-level severity scale. A modified Delphi process involving 29 US-based sickle cell disease experts was conducted over three virtual rounds (from Oct 20 to Nov 8, 2023; from June 26 to Aug 1, 2024; and from Nov 6, 2024, to Jan 7, 2025), with the use of a 9-point Likert scale ratings and iterative feedback. An in-person consensus workshop was then held in Memphis, TN, USA on Jan 16-17, 2025. This workshop was funded by the project's NIH grant (1R01CA270157-01). The final classification includes 53 clinical outcomes, each with diagnostic criteria, grades, and temporal patterns. This standardised, consensus-driven system provides a new benchmark for assessing sickle cell disease severity, with applications in clinical trials, disease burden assessment, and predictive modelling.