BackgroundAntimicrobial resistance is fueled by inappropriate prescribing and use of antibiotics. Global and national strategies support rational and adequate use of antibiotics to retain treatment options and fight resistances. In Germany, the ARena project (Sustainable reduction of antibiotic-induced antimicrobial resistance) was intended to promote the rational and appropriate use of antibiotics for acute non-complicated infections by addressing physicians, care teams and patients through multiple interacting interventions. This paper presents patterns of antibiotics prescribing for patients with acute non-complicated infections in participating primary care networks prior to the start of the ARena project, explores variation across subgroups of patients and draws comparisons to reference groups which represent standard care. MethodsIn mixed logistic regression models, we explored factors associated with the proportion of patients with acute non-complicated infections consulting primary care practices who received an antibiotic prescription. Secondary outcomes concerned the prescription of different types of antibiotics. Descriptive methods were used to summarize the data referring to primary care networks, reference groups, and subgroups. ResultsAcross all observed cases, antibiotic prescription rates were 31.7% in reference groups and 32.0% in primary care networks. Being the largest group of physicians observed, General practitioners prescribed antibiotics more frequently than other medical specialist groups (otolaryngologists vs. General practitioners OR=0.465 CI=[0.302; 0.719], p<0.001, pediatricians vs. General practitioners: OR=0.369 CI=[0.135; 1.011], p=0.053). Quinolone prescription rates were moderate (8.1% in reference groups and 9.9% in primary care networks). Patients with comorbidities had a higher likelihood of receiving an antibiotic and quinolone prescription and were less likely to receive a recommended substance. Younger patients were less likely to receive antibiotics (OR=0.771 CI=[0.636; 0.933], p=0.008). Female gender was associated with higher rates of antibiotic prescriptions compared to males (OR=1.293 CI=[1.201, 1.392], p<0.001).Conclusion Prior to the ARena project, observed antibiotic prescription rates for acute non-complicated infections were moderate, but there was still room for improvement. The use of recommended substances was low which indicates a need for creating stronger awareness of guideline-conform use of antibiotics.