Mobius FX, an add-on software module from Mobius Medical Systems™ for intensity-modulated radiation therapy (IMRT) quality assurance (QA), uses linac treatment logs to efficiently calculate and verify the 3D dose delivered to patients. An advantage of the Mobius FX module is that it does not require device positioning. In this study, we compared the Mobius FX with another QA option, ArcCheck, a...