THROAT CULTURING has many variables, especially the media used and the atmosphere of incubation, that affect the sensitivity of the culture method used as the reference method to evaluate a given streptococcal antigen detection system. A study of an antigen detection system that does not consider these might be biased. If a study uses an insensitive "gold standard" culture method to evaluate a rapid method, this can result in the antigen detection system being evaluated erroneously to appear to be as sensitive as and, possibly, a valid substitute for the more time-consuming throat cultures.
In a study reported in this issue, Schlager et al1 paid careful attention to the complexities of throat culture techniques to conduct a thorough evaluation of a new optical immunoassay for the direct detection of group A β-hemolytic streptococci (GABHS) antigen in throat specimens. Because our article2 and most of the studies cited in