Abstract
All 431 children and adolescents in this study had had one or more definite attacks of rheumatic fever and were distributed by a statistically controlled method of random selection into 3 groups, each assigned to a different prophylaxis regimen. The regimens under study were daily oral sulfadiazine, 1 g; daily oral potassium penicillin G, 200,000 units; and monthly injections of benzathine penicillin G, 1,200,000 units. The randomization method made the 3 patient groups comparable in age, cardiac status, and time interval since the rheumatic attack preceding admission to the study. They were also comparable in race, ethnic group, and number of preceding attacks of rheumatic fever. The 3 groups maintained prophylaxis for the same mean number of years. No major systemic sensitivity reaction to any of the 3 prophylactic agents was encountered. The 2 groups on oral regimens maintained approximately the same degree of fidelity to their programs, but neither of them maintained prophylaxis as well as the group receiving the parenteral preparation. The difficulties inherent in measuring fidelity of patients to an oral prophylaxis program were evident early in the study. No truly objective method could be evolved. A carefully devised interview technique proved the most valuable of the techniques employed.