1. DIP is actually to use the method of big data to discover the inherent law and correlation between disease and treatment by analyzing the massive medical record data in the real world, to establish the evaluation model of the influencing factors of disease severity and medical behavior norms on medical services, and to construct the standard system and correction system of disease combination, so as to objectively reflect the disease severity, treatment complexity, resource consumption level and clinical behavior norms. There is such a metaphor, which vividly describes the relationship between DRG and DIP: It's like two young people, one of whom (DRG) has money at home. After graduation, he first buys a big house of 15 square meters, and then he will get it in one step for the rest of his life; Another young man (DIP), with poor family conditions, bought a small house or rented a house after work to make a transition. Finally, I want to buy a 15-square house. According to the reality of China, there will be more people buying small houses and renting houses, and fewer people will do it in one step, but the ultimate goal is the same.

2. Medical insurance, in the traditional sense, refers to the collection of medical insurance funds among certain insured people in a certain area through policies and regulations with enforcement or voluntary contracts.

3. Medical insurance originated in Western Europe and can be traced back to the Middle Ages. With the success of the bourgeois revolution, family workshops were replaced by large industries, and modern industrial teams appeared. Due to the harsh working environment, the occurrence of epidemic diseases and industrial accidents makes workers require corresponding medical care. However, their wages are low, and it is difficult for individuals to pay medical expenses. So workers in many places spontaneously organized themselves to raise some funds for expenses when they were sick. But this form is not very stable, and it is small in scope, and its ability to resist risks is very low. At the end of 18th century and the beginning of 19th century, private insurance developed in Western Europe and became an important way for the state to raise medical funds.

4. Medical insurance has the basic characteristics of social insurance, such as compulsion, mutual assistance and sociality. Therefore, the medical insurance system is usually legislated and enforced by the state, and a fund system is established. The expenses are paid by both the employer and the individual, and the medical insurance premium is paid by the medical insurance institution to solve the medical risks caused by the illness or injury of the workers.