Comparison of tests for streptococcal pharyngitis.

Rapid streptococcal antigen detection tests are now an alternative to throat cultures for diagnosing group A streptococcal pharyngitis. By applying existing knowledge to 1,000 theoretical patients, this study compares the diagnostic accuracy, costs, and benefits of "gold standard" throat cultures, less specific office cultures, and rapid streptococcal tests. With the new rapid tests, appropriate treatment for streptococcal pharyngitis can be started promptly without waiting for a culture result. Benefit-cost analysis of existing data shows that rapid tests have the potential to be more efficient than throat cultures in minimizing medical costs and time lost because of illness. These conclusions remained true over widely ranging assumptions about streptococcal prevalence, carrier rate, rheumatic fever attack rate, test cost, and test accuracy.