What is Fecal Occult Blood Test?
Also written as：Fecal Occult Blood ／ Fecal Occult Blood Reaction
The fecal occult blood test checks for invisible trace amounts of blood mixed in the stool and serves as the foundation of colorectal cancer screening. In Japan, it is standard practice to collect stool samples on two separate days using an immunochemical method. The test is minimally burdensome, and a positive result leads to further diagnostic evaluation such as colonoscopy.
Reference range guideline
Normally negative (−). A positive result on even one of the two days indicates the need for further diagnostic testing.
* Reference ranges vary by testing facility, measurement method, age, sex, and other factors. Please check the reference range printed on your result sheet.
How to interpret an out-of-range result
A positive result may sometimes be caused by hemorrhoids and similar conditions; however, it is important not to self-diagnose and to undergo further diagnostic testing such as a colonoscopy.
Related tests and conditions
Frequently asked questions
I've heard that a positive fecal occult blood result is often due to hemorrhoids — do I still need to see a doctor?
Related terms
Sources & references
This page provides general information only and is not intended for diagnosis or treatment. Please consult the physician at your chosen facility regarding the interpretation of your health checkup results.