An observation method that the hospital regularly knows the changes of patients' condition through communication or other means to guide patients' rehabilitation. Follow-up can improve the service level of the hospital before and after treatment, at the same time, it is convenient for doctors to follow up and observe patients, master first-hand information for statistical analysis and accumulate experience, and it is also conducive to the development of medical research and the improvement of the professional level of medical workers, so as to better serve patients.