Rheumatoid Factor (RA) Test
This page explains the rheumatoid factor (ra) test, what it measures, and how to arrange it. The rheumatoid factor (RF) test checks for an antibody that can be present in autoimmune conditions, especially rheumatoid arthritis. It is ordered when a person has joint pain, swelling, or stiffness that might be due to an autoimmune disease.
- Sample type
- blood
- Category
- Autoimmune
- Turnaround
- 1-3 business days
- Price
- $198
- Referral
- Not required
The rheumatoid factor (RF) test checks for an antibody that can be present in autoimmune conditions, especially rheumatoid arthritis. It is ordered when a person has joint pain, swelling, or stiffness that might be due to an autoimmune disease.
What it measures
- Rheumatoid factor (RF) — An antibody that may be elevated in rheumatoid arthritis and other conditions.
- RF titer — A measure of how much RF is present, reported as a number or dilution.
- Isotype (IgM, IgG, IgA) — Some tests specify which type of RF antibody is present.
Who it is for
A primary care doctor or rheumatologist typically orders this test when evaluating joint symptoms or suspected autoimmune disease.
Preparation
No fasting or special preparation is usually needed for the rheumatoid factor test.
Results and what they mean
Results are reported as a value with a reference range, often as negative or positive. A positive result does not confirm a diagnosis, and a negative result does not rule it out. Only a clinician can interpret your results in the context of your symptoms and other tests. This is general information, not medical advice.
How to order this test
- Choose the test and place a confidential order online.
- Select a certified collection site and pick a time that suits you.
- Have your specimen collected — most draws take only a few minutes.
- Review results in a secure portal, typically within 1–3 days.
Preparation, hours, and pricing vary by site; confirm details directly with the lab before your visit.
Availability by state
Direct-access online ordering for the rheumatoid factor (ra) test is available in most states. It is currently unavailable in 6 states:
Everywhere else you can order confidentially and collect your sample at a certified site. Browse by state →
Frequently asked questions
What does a positive rheumatoid factor test mean?
It means the antibody was found in your blood. It can occur in rheumatoid arthritis and other conditions, so your doctor will consider your symptoms and other tests.
Can I have rheumatoid arthritis with a negative test?
Yes. Some people with rheumatoid arthritis do not have a positive rheumatoid factor test, so doctors may order other tests.
Do I need to fast for this test?
No, fasting is not required for the rheumatoid factor test.
How long does it take to get results?
Results are typically available within 1 to 3 business days.