Invasive testing methods (i.e. histology, rapid urease testing, and culture) are based on endoscopy and biopsy. These techniques are reserved for patients who require endoscopy because of alarm signs or who have new symptoms that develop after the age of 50 years. For other patients who have ulcer-like dyspepsia or other gastrointestinal signs and symptoms that suggest H. pylori infection or PUD, initial noninvasive testing is appropriate.