The proposed absorbed dose per MU-based method enables comprehensive small-field dosimetry evaluation by incorporating absolute dose verification into the credentialing process. This approach effectively identifies calibration inconsistencies that are not detectable using traditional relative dose factor methods. Its application across a large cohort of institutions demonstrated high accuracy and inter-institutional consistency, reinforcing its utility as a practical QA tool in SBRT clinical trials. By enhancing standardization in RTPS performance and linac output verification, this method strengthens the foundation of safe and reliable SBRT implementation in multi-center clinical research.
Kawahara et al. (Wed,) studied this question.