editorial

Abstract

Medical devices are playing a significant role in modern medicine. Devices are divided into four classes according to their risk levels. Class 1 are general medical devices whose risk levels are extremely low, such as in vitro diagnostic devices. Class 2 are controlled medical devices whose risks are relatively low such as MRI devices or electronic endoscopes. Class 3 are specially controlled medical devices whose risk levels are relatively high such as dialyzer. And Class 4 are invasive devices threatening patients’ lives.