CMO Letter to Reduce Unnecessary Antibiotic Prescribing and Broad Spectrum Prescribing Winter 2018-9 (CMO2018-9)

This trial aims to reduce unnecessary prescription of antibiotics and broad spectrum antibiotics by general practitioners (GPs) in England. Unnecessary prescriptions are defined as those that do not improve patient health outcomes. The intervention is to send GPs a letter from the Chief Medical Officer (CMO) that gives feedback on their practice's prescribing levels. Specifically the sample was GPs whose practices whose prescribed more than 1.161 items per STAR-PU or whose practices prescribed more that .965 items per STAR-PU and greater than 10% broad spectrum items. The intervention groups received a letter telling them they are among the highest prescribers of either their total or broad spectrum antibiotics, with a graph showing their prescribing compared to average prescribing ("their peers"). The letter also contained a leaflet to help GPs discuss self-care advice with patients and some advice to use delayed prescriptions. The investigators hypothesize that the antibiotic prescribing rate in will be lower for the treatment group compared to the control group, following the receipt of the letter.