[Secretory IgA: quality control of the titration method]

In order to verify if the method for the titration of salivary secretory IgA (s-IgA) by the technical of radial immunodiffusion is trustworthy, have been carried out the precision tests in the series and among the series in two saliva samples with very different s-IgA concentrations, and precision and accuracy tests in the series and among the series using a solution with a known titre of IgA. The results of the first battery tests have shown a precision ranging from 93.04 to 95.43%. The results of the tests of the second battery have shown a precision ranging about 96% and an accuracy about 97%. The tested method is, therefore, sufficiently trustworthy.