Rheumatoid Factor, Quantitative
A blood test that measures rheumatoid factor antibodies, which may be elevated in rheumatoid arthritis and several other conditions.
["A positive result can support a diagnosis of rheumatoid arthritis, but it must be interpreted with symptoms and other tests."]
Key facts at a glance
- LOINC
- 30647-2
- Short code
- RF BDs+GB Views W contr via T-tb
- Synonyms
- RF BDs+GB Views W contr via T-tb
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- rf
- CPT
- 86430
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
Rheumatoid factor (RF) is an antibody that can be measured in a blood sample. Some people with rheumatoid arthritis produce RF, although many people with the disease do not.
Why might I need this test?
This test may be used to help evaluate joint pain, swelling, or stiffness when an autoimmune condition is suspected. It is often considered along with physical findings and an anti-cyclic citrullinated peptide antibody test.
How is the test performed?
A blood sample is analyzed in the laboratory, commonly using an immunoassay or another antibody-detection method. The exact specimen and method depend on the laboratory that performs the test.
How do I prepare for the test?
Special preparation is usually not required, and fasting is generally unnecessary unless the ordering clinician gives different instructions. Do not stop taking medicines without medical advice.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
An elevated or positive RF result can occur in rheumatoid arthritis, but it may also be present with other autoimmune diseases, certain infections, or other health conditions. RF can occasionally be detected in people without a current rheumatologic disease. Results should therefore be interpreted with symptoms, examination findings, and other laboratory tests.
Short name
Rheumatoid factor (RF)
Frequently asked questions
Does a positive rheumatoid factor mean I have rheumatoid arthritis?
Can someone with rheumatoid arthritis have a negative RF result?
What other test is commonly used with rheumatoid factor?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy