The reproducibility of an enzyme-linked immunosorbent assay for detection of Chlamydia pneumoniae-specific antibodies.
With use of an enzyme-linked immunosorbent assay (ELISA), Chlamydia pneumoniae immunoglobulins were detected in a consecutive series of patients' sera (n = 122 for IgA and IgG; n = 138 for IgM). When the ELISA tests were repeated, the percentage disagreements were 12%, 16% and 10% for C. pneumoniae IgA, IgG and IgM, respectively. The reproducibility of the ELISA, expressed as kappa values, for IgA, IgG and IgM was 0.73, 0.60 and 0.53, respectively (p < 0.001). It was concluded that the ELISA had good reproducibility for detecting C. pneumoniae IgA, and moderately good reproducibility for detecting C. pneumoniae IgG and IgM.