Table 4.

A summary of clinical studies for pretreatment EPID based PSQA.

System	Author	Tests performed	Results
Dosimetry Check (RadCalc EPID)	Chendi et al. 2021	20 FFF plans, compared to Octavius phantom measurement and TPS calculation (in-patient CT)	Poor correlation in gamma-pass rates
Epiqa	Fogliata et al. 2011	295 patient VMAT plans, 5 centers	Mean gamma 97.1±2.4% at 3%,3mm
Epiqa	Nicolini et al. 2013	74 arcs VMAT FFF	Similar to non FFF if > 150 cm EPID distance
Portal Dosimetry	Howell et al. 2008	152 patient IMRT plans (1152 fields)	Mean gamma value tolerances established
Portal Dosimetry	Iori et al. 2010	23 arcs VMAT	Same results as IMRT but using external EPID fixation device
Portal Dosimetry	Bailey et al. 2012	Prostate, head neck, breast IMRT (126 fields)	Off axis breast tangents lower results, may not adequately model off axis
Portal Dosimetry	Ballangrud et al. 2018	40 multitarget SRS deliveries	γ pass rate of greater than 95% for most fields at 3%/2 mm criteria with a 10% threshold
Portal Dosimetry	Covington et al. 2019	36 plans single-target SRS VMAT QA for at 10FFF energy	composite EPID image of the two arcs 3%/2 mm criteria with 10% threshold a 100% pass rate
Portal Dosimetry	Koo et al. 2020	200 breast IMRT plans	Average gamma passing rate of 98·4 ± 4·3 for 2%/2 mm symmetric plans and 89·7 ± 9·5 for 2%/2 mm asymmetric plans