Interlaboratory variability of the antiperinuclear factor (APF) test for rheumatoid arthritis

Clin Exp Rheumatol. Jan-Feb 1993;11(1):57-9.


The antiperinuclear factor (APF) test is as sensitive and specific for rheumatoid arthritis as the classical rheumatoid factor tests. Five European laboratories decided to perform a consensus study on the interlaboratory variability of the APF test. They used different donor cells, different conjugates and different criteria for positivity. However, the results differed by not more than one two-fold dilution step, when expressed in international units using WHO reference rheumatoid arthritis serum as the standard.

Publication types

  • Comparative Study

MeSH terms

  • Antibodies, Antinuclear / blood*
  • Arthritis, Rheumatoid / diagnosis
  • Arthritis, Rheumatoid / epidemiology
  • Arthritis, Rheumatoid / immunology*
  • Clinical Laboratory Techniques* / standards*
  • Consensus Development Conferences as Topic
  • Europe / epidemiology
  • Humans
  • Reference Standards
  • Reproducibility of Results
  • World Health Organization


  • Antibodies, Antinuclear
  • antiperinuclear factor