Competition in primary care and prescription of antibiotics in Norway
Appropriate use of antibiotics is an important strategy to combat the problem of growing antibiotic resistance rates. In order to follow this strategy, it is important to understand the determinants of antibiotic use. We analyse the potential link between competition among general practitioners (GPs) measured with the Herfindahl-Hirshman index (HHI) and regional antibiotic consumption in Norway in 2015 and 2016. We use the data about antibiotic consumption expressed by the number of prescriptions of antibiotics for systemic use (J01) and by the number of antibiotics for respiratory tract infections (phenoxymethylpenicillin (J01CE02), doxycycline (J01AA02), amoxicillin (J01CA04) and macrolides (J01FA)) per 1000 inhabitants. We apply multiple regression analysis to the data mentioned above and control for socioeconomic characteristics of the municipalities. Our findings suggest that competition may contribute to about 37-80 additional antibiotic prescriptions per 1000 inhabitants per year and 23-46 additional prescriptions per 1000 inhabitants of antibiotics for respiratory tract infections. Moreover, our estimations suggest that antibiotic prescription is significantly related to the average number of consultations per patient, the average length of the patient list, travel time to a pharmacy, income, and the share of women.