The recent publication of the new code of practice IEAA/AAPM TRS-483 introduces the use of output
correction factors to correct the changes in detector response in relative dosimetry of small photon
beams. In TRS-483, average correction factors are reported for several detectors at 6 and 10 MV
with and without
attening. These correction factors were determined by Monte Carlo simulation
or experimental measurements using several linacs of di erent brands and vendors. The goal of this
work was to validate the output correction factors reported in TRS-483 for a 6 MV (with and without
attening lter) of a TrueBeam STx® linac with Monte Carlo simulation for four radiation detectors
employed in the dosimetry of small photon beams and whose output correction factors were determined
using di erent radiation source than TrueBeam STx®: PTW®31010, PTW®31016, IBA®CC-01, and
IBA®SFD. The results show that Monte Carlo calculated output factors, and those reported in the
code of practice TRS-483 fully agree within 1%. The use of generic correction factors for a TrueBeam
STx® and the detectors studied in this work is adequate for small dosimetry static beams within the
uncertainties of Monte Carlo calculations and output correction factors reported in TRS-483.
Key words: TRS-483, Monte Carlo simulation, output correction factors, detector model, Phase
Space File, Latent Varianc
