Abstract: Objective To found the quantifiable index of "The severe degree of negligence" in describing the general severity degree of medical malpractice or medical dispute. Methods "The severe degree of negligence" can be calculated by the way of multiplying the coefficient of medical malpractice′s grade by the coefficient of responsibility degree. Results There are 15 grades of "The severe degree of negligence" through calculation, from the severest degree of 1 to the lightest degree of 20. Conclusion "The severe degree of negligence" can give an order of severe degree to different grade and different responsibility of medical malpractice. According to this order, the operation of medical malpractice and medical dispute settle will be easier and more rationality.

Key words: severe degree of negligence, medical malpractice, grade of medical malpractice, responsibility degree