Antibiotic resistance has become a major threat to global public health. It is driven by a multitude of factors, however one of the leading factors is antibiotic prescribing. Inappropriate antibiotic use and overuse of broad-spectrum antibiotics can lead to the development of resistant strains. Since in Malta the vast majority of antibiotics are acquired through prescription, targeting providers' prescribing behavior is an important strategy needed to try to curb antibiotic overuse and resistance.

The aim of this study is to evaluate the effect of a multifaceted social marketing intervention in changing general practitioners' (GPs) antibiotic prescribing behavior for patients with acute respiratory tract complaints in Malta. This quasi-experimental intervention study using an interrupted time series design includes three phases; a formative pre-intervention phase, an intervention phase and post-intervention evaluation phase, and will last a total of four years.

During the pre-intervention phase, various stakeholders, including GPs, pharmacists and parents will be interviewed in order to get a better contextual understanding of antibiotic use in Malta. A 1-year baseline surveillance system will also be set up to collect actual diagnosis-specific antibiotic prescribing by GP. This data will, at a later stage, be used to measure the change in antibiotic prescribing behavior post-intervention stage. GPs stage of behavior change and intention to prescribe antibiotics will also be measure pre-intervention using questionnaires based on the theory of planned behavior and the transtheoretical model.

The intervention stage will last 6 months and will include multiple components, including, delayed prescription pads, educational sessions, educational materials for patients and distribution of antibiotic guidelines. The intervention will be monitored closely through numerous process indicators.

Following the intervention, GPs' stage of change and intention to prescribe antibiotics will be re-measured using the same questionnaire used pre-intervention. Surveillance data collection will be also be resumed and will provide data to measure the primary outcome as well as additional secondary outcomes.

The primary outcome of interest is the change in the rate of antibiotic prescribing for patients presenting with an acute respiratory tract complaint.

Inclusion Criteria:

• All actively practicing general practitioners and trainees specializing within family medicine are eligible to participate regardless of whether they work on a part-time or full-time basis, or in the public and/or private sectors

Exclusion Criteria:

• General practitioners who are no longer actively working