Online dose verification is a crucial step in ensuring safe and effective implementation of intensity-modulated radiotherapy (IMRT). Traditionally, dose verification is performed using phantom measurements before the first treatment. However, this method does not allow for real-time monitoring and evaluation of all treatments for patients. To address this limitation, the use of electronic portal imaging devices (EPID) during accelerator operation or the multi-leaf collimator (MLC) running log files can be employed to obtain various parameters during the execution of radiotherapy plans. This allows for patient dose verification, as well as monitoring and evaluation of the plan execution status of all treatments for patients. This set of guidelines aims to systematically introduce the principles, methods, steps, technical requirements, result analysis, and evaluation of the online dose verification method, providing guidance to units and individuals on how to correctly and rationally use this method and improving the efficiency and coverage of IMRT dose verification. Ultimately, the goal is to ensure the safety and accuracy of treatment.

Radiotherapy, intensity-modulated; Online dosimetric verification; γ pass rate; Log files; Electronic portal imaging device