Association between use of rapid antigen detection tests and adherence to antibiotics in suspected streptococcal pharyngitis

Objective. Few studies have analysed adherence to antibiotic treatment in pharyngitis. The aim of this study was to evaluate the association of rapid antigen detection tests (RADT) and treatment adherence among patients 18 years of age or over with pharyngitis treated with different antibiotic regimens. Design. Prospective study from 2003 to 2008. Setting. Office-based physician practices. Intervention. The adherence of patients prior to the use of RADTs - no test was available until mid-2006 - was compared with the adherence associated with the use of RADTs. Subjects. Patients with suspected streptococcal pharyngitis. Main outcome measures. Patient adherence was assessed by electronic monitoring. The adherence outcomes considered were antibiotic-taking adherence, correct dosing, and good timing adherence during at least 80% of the antibiotic course. Results. A total of 196 patients were recruited. The percentage of container openings was 77.9%+/- 17.7%, being significantly higher for patients in whom the RADTs were performed compared with those in whom this test was not undertaken (80.1% vs. 70.8% for thrice-daily antibiotic regimens and 88.1% vs. 76.5% for twice-daily regimens; p < 0.01). The other variables of adherence were also better among patients undergoing RADT in both those who took at least 80% of the pills (71.3% vs. 42.2%; p < 0.001) as well as those with good timing adherence (52.5% vs. 32.8%; p < 0.01). Furthermore, correct dosing was always greater when the patient had undergone an RADT. Conclusion. Adherence to antibiotic treatment is higher when an RADT is carried out at the consultation prior to administration of antibiotic treatment.