High Overall CRC Diagnostic Accuracy for Home Stool Test
(HealthDay News) — Fecal immunochemical tests (FITs) have moderate sensitivity, high specificity, and high overall diagnostic accuracy for detecting colorectal cancer (CRC), according to research published in the February 4 issue of the Annals of Internal Medicine.
Jeffrey K. Lee, MD, of the University of California in San Francisco, and colleagues conducted a systematic review and meta-analysis of the literature to assess the diagnostic accuracy of FITs for detecting CRC in asymptomatic, average-risk adults.
The researchers found that, for CRC screening, the overall diagnostic accuracy of FITs was 95% (95% confidence interval [CI], 93 to 97%), the pooled sensitivity was 0.79 (95% CI, 0.69 to 0.86), and the pooled specificity was 0.94 (95% CI, 0.92 to 0.95). Using a lower assay cutoff value for a positive test result, such as less than 20 µg/g, improved sensitivity to 0.89 (95% CI, 0.80 to 0.95) but decreased specificity.
"FITs are moderately sensitive, are highly specific, and have high overall diagnostic accuracy for detecting CRC. Diagnostic performance of FITs depends on the cutoff value for a positive test result," the authors conclude. "Health systems wishing to optimize use of a quantitative FIT should consider the tradeoff between increasing sensitivity (by lowering the cutoff threshold for a positive test) and the resulting increase in the number of positive test results, which will have a greater effect on colonoscopy resources."