Report Dose-To-Medium In Clinical Trials Where Available; A Consensus From The Global Harmonisation Group To Maximize Consistency

Purpose: To promote consistency in clinical trials by recommending a uniform framework as it relates to radiation transport and dose calculation in water versus in medium.Methods: The Global Quality Assurance of Radiation Therapy Clinical Trials Harmonisation Group (GHG; www.rtqaharmonization.org) compared the differences between dose to water in water (D-w,D-w), dose to water in medium (D-w,D-m), and dose to medium in medium (D-m,D-m). This was done based on a review of historical frameworks, existing literature and standards, clinical issues in the context of clinical trials, and the trajectory of radiation dose calculations. Based on these factors, recommendations were developed.Results: No framework was found to be ideal or perfect given the history, complexity, and current status of radiation therapy. Nevertheless, based on the evidence available, the GHG established a recommendation preferring dose to medium in medium (D-m,D-m).Conclusions: Dose to medium in medium (D-m,D-m) is the preferred dose calculation and reporting framework. If an institution's planning system can only calculate dose to water in water (D-w,D-w), this is acceptable. (C) 2021 The Authors. Published by Elsevier B.V.