Symptoms of the upper gastrointestinal tract (including those of esophageal, gastric, and duodenal origin) lack specificity and, depending on the severity and type of symptoms, cannot be clearly distinguished from gastroesophageal reflux, gastritis, gastric ulcer, duodenal ulcer, upper gastrointestinal tumor, or simple dyspepsia, and therefore require further examination or therapeutic observation. According to clinical epidemiological studies, endoscopy is needed for our Han population with upper gastrointestinal symptoms, older than 45 years of age, or (although they may be younger than 45 years of age) with so-called alarming symptoms such as vomiting blood, black feces, wasting, and severe pain.