Rheumatoid Factor Test

What is the rheumatoid factor test?

This is a test to determine if you have rheumatoid factor, a kind of antibody, in your blood.

Why is this test done?

The test is done to help diagnose rheumatoid arthritis. Rheumatoid arthritis is a disease that causes pain, stiffness, swelling of the joints, and sometimes joint damage.

How do I prepare for this test?

No special preparation is needed for this test.

How is the test done?

A small amount of blood is taken from your arm with a needle. The blood is collected in tubes and sent to a lab.

Having this test will take just a few minutes of your time. There is no risk of getting AIDS, hepatitis, or any other blood-borne disease from this test.

How will I get the test result?

Ask your heath care provider when and how you will get the result of your test.

What does the test result mean?

A positive test result means that you have rheumatoid factor in your blood. If you have painful joint swelling and other symptoms along with other abnormal blood test results, you may have rheumatoid arthritis. If you have no symptoms, the test is not very helpful. Many healthy people test positive for small amounts of rheumatoid factor, but they never develop rheumatoid arthritis or other diseases.

If you have a negative rheumatoid factor test result and no symptoms of arthritis, you probably do not have rheumatoid arthritis. However, if you have a negative test result but you have symptoms of arthritis and abnormal results for other blood tests, you may have rheumatoid arthritis or a related condition. Some people with rheumatoid arthritis never test positive for rheumatoid factor. In this situation other tests can help determine that the problem really is rheumatoid arthritis, even with a negative rheumatoid factor.

What if my test result is not normal?

Test results are only one part of a larger picture that takes into account your medical history and current health. Sometimes a test needs to be repeated to check the first result. Talk to your healthcare provider about your result and ask questions.

If your test result is not normal, ask your healthcare provider:

• if you need additional tests
• when you need to be tested again.