External Validity: Poor. Studies on populations in high-risk areas may not be applicable to low-risk areas such as the United States.
Based on solid evidence, screening would result in uncommon but serious side effects associated with endoscopy, which may include perforation, cardiopulmonary events, aspiration pneumonia, and bleeding requiring hospitalization.
False-positive tests are also common in association with serum pepsinogen or gastric photofluorography.
Magnitude of Effect: Good evidence for rare but serious harms.
Description of the Evidence
Study Design: Evidence obtained from screening programs and from case series.
Internal Validity: Fair.
Consistency: Inadequate evidence.
External Validity: Poor.
Leung WK, Wu MS, Kakugawa Y, et al.: Screening for gastric cancer in Asia: current evidence and practice. Lancet Oncol 9 (3): 279-87, 2008.