What does a positive guaiac test look like? - TimesMojo

How to Take a Stool Sample with a Stool Collection Kit

A “normal” stool report can be reassuring — but it’s important to understand what these tests are actually designed to detect. There are two common methods to check for hidden blood in stool: 🔎 Guaiac-based test (gFOBT): Detects peroxidase activity of hemoglobin. Sensitivity ~50–70% for cancer (lower for polyps), specificity ~90–95%. Can be affected by red meat and certain vegetables. 🧪 FIT (Fecal Immunochemical Test): Detects human globin specifically. Sensitivity ~75–85% for colorectal cance