Table 7.

Testing for interference in suspected samples.

□ Use of an alternate immunoassay that preferably uses antibody raised to a different species □ Measurement before and after addition of a blocking reagent, especially bovine, or a series of concentrations of the blocker, or a combination of blockers from different species □ Measurement of dilutions of the sample using the manufacturer's diluent containing non-immune globulin □ Sample pre-treatment (see Table 6) □ Radioimmunoprecipitation of labelled thyroid hormones to detect anti-T3 and anti-T4 autoantibodies