Rheumatoid Factor: About This Test
What is it?
A rheumatoid factor (RF) blood test measures the amount of the RF antibody in your blood. The RF antibody can attach to normal body tissue, causing damage.
A high RF level can be caused by several autoimmune diseases, including rheumatoid arthritis, and some infections. Sometimes an elevated level of RF is present in healthy people.
Why is this test done?
A test for rheumatoid factor is done to help support a diagnosis of rheumatoid arthritis.
How do you prepare for the test?
In general, there's nothing you have to do before this test, unless your doctor tells you to.
How is the test done?
A health professional uses a needle to take a blood sample, usually from the arm.
How long does the test take?
The test will take a few minutes.
What happens after the test?
- You will probably be able to go home right away.
- You can go back to your usual activities right away.
Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.
Where can you learn more?
Go to https://www.healthwise.net/patientEd
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Current as of: May 13, 2023
Author: Healthwise Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
