An analysis of the cost-effectiveness of pharyngitis management and acute rheumatic fever prevention.

The cost-effectivness of preventing primary acute rheumatic fever attacks by oral or benzathine penicillin treatment was analyzed for both epidemic and endemic streptococcal pharyngitis situations. Decision analysis was used: the probabilities and the outcome values were calculated from published data. Three penicillin strategies were compared: (A) treating only patients with group A streptococci-positive throat cultures; (B) treating all patients; (C) treating none of the patients. In the epidemic situation it is medically most effective and least costly to treat all patients with penicillin (Strategy B). In the endemic situation, Strategy B is also most cost-effective when oral penicillin is used in patient populations where the positive throat culture yield is at least 20%. Strategy A is optimal when the yield is between 5% and 20%; below a 5% yield, Strategy C is appropriate. For any individual patient, it is possible that choice of the most cost-effective treatment strategy could be based on the patient's clinical findings.