# Rheumatoid Factor (RF)

> This test measures the level of rheumatoid factor, a protein produced by your immune system that can mistakenly attack healthy body tissue. It helps show whether symptoms like joint pain, stiffness, or swelling may be caused by an autoimmune reaction rather than general wear and tear. Doctors use these results to help distinguish rheumatoid arthritis from other types of joint disorders or inflammatory conditions. However, a high level does not confirm a diagnosis by itself, as elevated results can also appear in other infections or even in healthy people.

- Labcorp code: 006502
- Category: [Autoimmunity](https://app.picardo.health/labs/tests/autoimmunity.md)
- Price: shown at checkout, before payment.
- Blood draw: free at a Labcorp location, or $75.00 at home.
- Order link: https://app.picardo.health/labs/order?tests=006502&ref=assistant
- Already in these panels: [Thyroid & Autoimmunity](https://app.picardo.health/labs/panels/thyroid-autoimmunity.md)

## About ordering

A licensed physician reviews every order before any test is run, and results arrive in the person's Picardo account. Ordering is open to adults 18 and over in the US, except New York, New Jersey, Rhode Island, Pennsylvania, Maryland, Massachusetts, Hawaii and Maine. General health information, not medical advice.