Validity and Reliability of the Japanese Version of the Rome III Diagnostic Questionnaire for Irritable Bowel Syndrome and Functional Dyspepsia

BACKGROUND/AIMS: Reliable diagnostic instruments for measuring the presence of functional gastrointestinal disorders based on the Rome III criteria have been lacking in Japan. The aims of the present study were to translate and validate the Rome III diagnostic questionnaire which was widely used in Western countries. METHODS: The original version of Rome III diagnostic questionnaire was translated from English into Japanese through 3 independent forward translations, resolution, back translation and reconciliation of the differences. Forty-nine patients with irritable bowel syndrome (IBS), 32 patients with functional dyspepsia (FD) and 56 subjects without any current GI symptoms as controls were recruited from three hospitals located in different regions of Japan and completed the IBS and FD diagnostic modules twice within 14 days. Kappa statistic was used to assess test-retest reliability. The sensitivity and specificity of each diagnostic module for distinguishing IBS or FD patients from controls was tested. RESULTS: Median kappa statistics were 0.63 for the translated IBS diagnostic module and 0.68 for the FD module. The sensitivity, specificity, and positive predict value of the IBS module against physician diagnosis was 61.2%, 100%, and 100% and those of the FD module was 53.2%, 98.2%, and 94.4%, respectively. Meanwhile, IBS patients were significantly more likely to report blood in stools compared to controls (18.4% vs 1.8%, P < 0.01). CONCLUSIONS: The IBS and FD diagnostic modules on the Japanese version of the Rome III diagnostic questionnaire are valid and reliable. Further studies are warranted to elucidate the diagnostic utility of the red flag questionnaire.

Prevalence of Subjects at a High or Very High Risk of Gastric Cancer in Japan

BACKGROUND/AIMS: The presence of Helicobacter pylori (H. pylori) infection represents a high-risk state of gastric cancer, but the risk is even higher in gastric atrophy. H. pylori stool antigen (HpSA) and serum pepsinogen (PG) tests are useful tools for screening present infection and gastric atrophy, respectively. To determine the prevalence of subjects at a high risk (HpSA+ or PG+) or very high risk (PG+) of gastric cancer in Japan, we applied the two tests to a general population. METHODS: The subjects included 311 volunteers. We used Meridian HpSA ELISA for the HpSA test and Pepsinogen RIA Beads for the PG test. PG I at 50% of those older than 40 years). Half of the subjects older than 60 years were PG+. CONCLUSIONS: In Japan, more than 50% of general population aged > or =40 years is at a high risk of gastric cancer, and half of the population aged > or =60 years is at a very high risk.