A useful method for determining class-specific rheumatoid factors with computerized analyses of data

J Immunol Methods. 1988 Feb 24;107(1):93-101. doi: 10.1016/0022-1759(88)90014-2.


A simple and sensitive enzyme-linked immunosorbent assay (ELISA) was developed to determine rheumatoid factors (RFs) of IgG, IgA and IgM class. Standardisation was performed with a standard reference serum for IgM-RF, calibrated according to the WHO preparation, and with the serum of a patient containing high levels of IgA- and IgG-RF. The sigmoidal shaped calibration curve was fitted with a computerized four parameter logistic model with simplified mathematical computations. This method provided to be more accurate for measuring RF levels, as judged by the smaller residuals, than logit or log-linear transformations. The considerable reduction in processing time, which is obtained by the computerized analysis of data, makes this method of class-specific RF determination suitable for routine analysis.

MeSH terms

  • Enzyme-Linked Immunosorbent Assay / methods
  • Humans
  • Immunoglobulin A / analysis*
  • Immunoglobulin G / analysis*
  • Immunoglobulin M / analysis*
  • Pepsin A
  • Rheumatoid Factor / analysis*
  • Software


  • Immunoglobulin A
  • Immunoglobulin G
  • Immunoglobulin M
  • Rheumatoid Factor
  • Pepsin A