Legal basis: Article 4 of the Regulations on Handling Medical Accidents in People's Republic of China (PRC) is divided into four levels according to the degree of personal injury to patients: first-class medical accidents: those that cause death and severe disability to patients; Secondary medical accident: moderate disability and severe dysfunction caused by organ and tissue damage; Third-class medical accidents: causing mild disability of patients, organ and tissue damage leading to general dysfunction; Four-level medical accidents: other consequences that cause obvious personal injury to patients. Specific grading standards shall be formulated by the health administrative department of the State Council.