A statistical approach to IMRT patient-specific QA.

Abstract

The intensity modulated radiation therapy (IMRT) patient-specific quality assurance (QA) (referred to as QA in this paper for simplicity) process is a time and resource intensive effort in every clinic. The use of a global QA tolerance criterion for all treatment sites may be too tight for some complex sites increasing false negatives and rejections of QA measurements which typically results in wasted efforts, treatment delays, and decreased efficiency. At the same time, other sites requiring a less complex plan might have a high false positive leading to approvals of QA measurements that actually need to be rejected. This work is an effort to adopt statistical tools to1. develop a tool to identify statistical variations in the process, monitor trends, detect outliers, and proactively identify drifts in the overall QA results;2. analyze the results of the QA process, identify similarities and differences between treatment plans of different treatment sites, and evaluate the possibility of site-specific tolerance levels for QA approval tolerances.