Objective. This study was aimed at evaluating the effect of two levels of intervention on the antibiotic prescribing in patients with common cold. Methods. Before and after audit-based study carried out in primary healthcare centres in Spain. General practitioners registered all the episodes of common cold during 15 working days in January and February in 2008 (preintervention). Two types of intervention were considered: full intervention, consisting in individual feedback based on results from the first registry, courses in rational antibiotic prescribing, guidelines, patient information leaflets, workshops on rapid tests -rapid antigen detection and C-reactive protein tests- and provision of these tests in the surgeries; and partial intervention, consisting of all the above intervention except for the workshop and they did not have access to rapid tests. The same registry was repeated in 2009 (postintervention). In addition, new physicians filled out only the registry in 2009 (control group). Results. 210 physicians underwent the full intervention, 71 the partial intervention and 59 were assigned to the control group. The 340 doctors prescribed antibiotics in 274 episodes of a total of 12,373 cases registered (2.2%).The greatest percentage of antibiotic prescription was found in the control group (4.6%). The partial intervention increased the antibiotic prescription percentage from 1.1% to 2.7% while only doctors who underwent the complete intervention lead to a significant reduction of antibiotics prescribed, from 2.9% before to 0.7% after the intervention (p