Overestimated Sensitivity of Fecal Immunochemical Tests in Screening Cohorts With Registry-Based Follow-up. (November 2019)

• Record Type: Journal Article
• Authors: Brenner, Hermann; Gies, Anton; Selby, Kevin
• Is Part Of: American journal of gastroenterology. Volume 114:Number 11(2019)
• Publication Date: 2019-11
• Subjects: Stomach -- Diseases -- Periodicals; Intestines -- Diseases -- Periodicals; Gastroenterology -- Periodicals; Gastrointestinal Diseases -- Periodicals; Electronic journals; Periodicals; 616.33
• DOI: 10.14309/ajg.0000000000000412
• Languages: English
• ISSNs: 0002-9270

Abstract

Abstract : OBJECTIVES: Several recent studies have reported very high estimates of sensitivity and specificity of fecal immunochemical tests (FITs) at seemingly high levels of precision using registry-based follow-up of participants in very large FIT-based screening programs. We aimed to assess the validity of estimates of diagnostic performance parameters derived by this indirect approach. METHODS: We modeled expected values of sensitivity and specificity of colorectal cancer detection in studies using the indirect approach and their deviation from true values under a broad range of plausible assumptions, and we compared these expected values with recently reported estimates of FIT sensitivity and specificity from such studies. RESULTS: Using a sensitivity of 75% and specificity of 93.6% (from studies using a direct approach, i.e., colonoscopy follow-up of all participants), the indirect approach would be expected to yield sensitivities between 84.5% and 91.1% and specificities between 93.4% and 93.6% under a range of realistic assumptions regarding colonoscopic follow-up rates of positive FITs and clinical manifestation rates of preclinical colorectal cancer. DISCUSSION: Very high sensitivities of FITs recently reported with seemingly very high levels of precision by several large-scale registry-based studies, which are in line with expected results based on our model calculations, are likely to be strongly overestimated and need to be interpreted with due caution.