Diagnostic accuracy of a single qualitative immunochemical fecal occult blood test coupled with physical measurements

摘要

Background We aimed to improve the sensitivity of immunochemical fecal occult blood test (I-FOBT) to screen colorectal neoplasm among average-risk adults.Methods This is a diagnostic cohort study.All health examination participants receiving a single qualitative I-FOBT and a screening colonoscopy from January 2010 to June 2011 were included.Stool specimens were collected for I-FOBT before colonoscopy.Using pathology as gold standard,significant colorectal neoplasm was defined as advanced adenoma or malignancy.Results A total of 1 007 health examinees were identified.Fifty-five (5.5％) had borderline positive (+/-) I-FOBT,while 38 (3.8％) had positive I-FOBT.Twenty-four (2.4％) had advanced adenoma,and five (0.5％) had carcinoma.Using borderline positive I-FOBT as cutoff value,the sensitivity and specificity for significant colorectal neoplasm were 34.5％ (95％ confidence interval (CI) 19.9％-52.7％) and 91.5％ (95％ Cl89.6％-93.1％),respectively.If combined with advanced age,high blood pressure (BP),and abdominal obesity,a fulfillment of either two criteria further increased the sensitivity to 72.4％ (95％ Cl54.3％-85.3％) with a specificity of 68.8％ (95％ Cl65.8％-71.6％).Conclusion The sensitivity of a single qualitative I-FOBT for the detection of significant colorectal neoplasm can be increased by coupling with age,BP,and abdominal obesity.