Rheumatoid Factor (RF)
Immunology
Sample and container requirements
Serum
Minimum volume required
4 ml Blood
Special requirements
None
Patient preparation
None
Sample viability
Stored at 4oC
Turnaround time
1day
Reference range
Up to 30 IU/mL = Negative 30-50= Weak Positive Greater than 50 IU/mL = Positive
Clinical guidance
https://labtestsonline.org.uk/tests/rheumatoid-factor
Notes
Images to go here
This information was last updated on 17 August 2026