Preferred Sample Type

Rheumatoid Factor (RF)

Suitable Specimen Types

  • Serum
5-10 mL

Sample Processing in Laboratory


Sample Preparation


Turnaround Time

1 day

Sample Stability

Stored at 4oC

Rheumatoid Factor (RF)

General Information

Rheumatoid factor is  a significant serological marker of rheumatoid arthritis and can occur in 50 -90% of patients with RA, however, 2-10 % of apparently healthy adults have been shown to have a positive rheumatoid factor and Rheumatoid factors can oocur in up to 50% of patients with infection. 

Patient Preparation



This method is suitable for serum samples only.

Reference Range

Up to 30 IU/mL = Negative

30-50= Weak Positive

Greater than 50 IU/mL = Positive


  • EQA Scheme?: Yes
  • EQA Status:

    UK NEQAS scheme for general autoimmune serology.

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HTA licence number is 12366

Protection of Personal Information – Laboratory Medicine comply with the Trust Data Protection Policy and have procedures in place to allow the Directorate and it’s employees to comply with the Data Protection Act 1998 and associated best practice and guidance.

The Trust Laboratories at Heartlands Hospital, Good Hope Hospital and Solihull Hospital were awarded UKAS (United Kingdom Accreditation Service) accreditation to the internationally recognised ISO 15189 standard in May 2015. For a list of accredited tests and other information please visit the test database
Tests not appearing on this scope are either under consideration or in the process of accreditation and so currently remain outside of our scope of accreditation. However, these tests have been validated to the same high standard as accredited tests and are performed by the same trained and competent staff.

For further information contact Louise Fallon, Quality Manager, 0121 424 1235

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