Inclusion Criteria:  Age ≥ 18 years old. Those who underwent upper gastrointestinal and small intestinal mucosal examination under magnetically controlled capsule endoscopy at Shanghai Changhai Hospital and Chinese PLA General Hospital after January 2020. Able to provide informed consent.  Exclusion Criteria:  Patients who fail to follow the prescribed procedures for magnetically controlled capsule endoscopy; Patients who only undergo gastric examination under magnetically controlled capsule endoscopy; Patients who only undergo small bowel examination under magnetic control capsule endoscopy; The patient's basic information in the database is incomplete； Patient fail to be followed up.