Advanced Physics for Brachytherapy 2018

Summary of TG-138 Report

• AAPM + ESTRO recommend GUM methods for expressing dosimetric uncertainties

• precision ≠ accuracy

• Type A (statistical: standard deviation of results) Type B (non-Type A uncertainties)

• low-E (8.7%, k =2)

high-E (6.8%, k =2)

• expanded uncertainty, k =2 (95% confidence 21/22)

• pre-Tx recommendations: S K

, exp, MC, vendors

• clinical practice uncertainties are larger