Fecal Immunochemical Tests Have "High Overall Diagnostic Accuracy" — Physician’s First Watch
Fecal Immunochemical Tests Have "High Overall Diagnostic Accuracy"
By Joe Elia
A meta-analysis on fecal immunochemical screening for colorectal cancer finds the tests moderately sensitive, but highly specific. The analysis appears in the Annals of Internal Medicine.
Nineteen studies showed the tests have a sensitivity of 0.79, a specificity of 0.94, a positive likelihood ratio of 13.10, and a negative likelihood ratio of 0.23. Those likelihood ratios could help rule in or rule out diagnoses.
Increasing the number of fecal samples did not affect sensitivity. Lowering the cutoff value for a positive result increased sensitivity, but at the cost of some specificity. The authors estimate that a cutoff value of less than 20 micrograms/gram gave the best balance of sensitivity (0.86) and specificity (0.91) with the lowest negative likelihood ratio (0.16).
Fecal immunochemical testing has an advantage in that patients don't need to restrict their diets or suspend drug intake beforehand.