 The great majority of the RADTs that are currently available have an excellent specificity of 95, compared with blood agar plate culture. This means that false-positive test results are unusual, and, therefore, therapeutic decisions can be made with confidence on the basis of a positive test result. Unfortunately, the sensitivity of most of these tests is 80-90, or even lower, compared with blood agar plate culture. It has been suggested that most of the false-negative RADT results occur for patients who are merely Streptococcus carriers and are not truly infected. However, early studies of first-generation RADTs demonstrated that a large proportion of patients with false-negative RADT results were truly infected with group A b-hemolytic streptococci and were not merely carriers.8 