What is the most effective diagnostic evaluation of streptococcal pharyngitis?

Standardized clinical decision rules, such as the Centor criteria, can identify patients with low likelihood of group A beta-hemolytic streptococ-cal (GABHS) pharyngitis who require no further evaluation or antibiotics (strength of recommendation [SOR]: A, based on validated cohort studies). For patients at intermediate and higher risk by clinical prediction rules, a positive rapid anti-gen detection (RAD) test is highly specific for GABHS (SOR: A, based on systematic reviews of diagnostic trials). A negative RAD test result, using the best technique, approaches the sensitivity of throat culture (SOR: B, based on retrospective cohort studies). In children and populations with an increased prevalence of GABHS and GABHS complications, adding a backup throat culture reduces the risk of missing GABHS due to false-negative RAD results (SOR: C, based on expert opinion)