Hi Mellat
You will easily get plenty of retrospective data out of your SGRT- system and/or offline review system for image evaluation about intra-and interfractional setup/BH- reproducibility for comparison between the groups with your daily practices. It is an advantage, if you have CBCTs available. Here is one good publication: Effects of Preparatory Coaching and Home Practice for Deep Inspiration Breath Hold on Cardiac Dose for Left Breast Radiation Therapy, Kim et al. 2018.
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