There is a great variability in the different primary care teams referral rate. And variability means inappropriateness somewhere in the process of care. The most important determinants of the variability are the attitude and knowledge of the professional, the existence and availability of evidence, the resources available and the professionals practice style. To improve the knowledge of the professionals could be a way to decrease the variability. Because of this, we have the aim to determinate the effectiveness of an educational intervention to improve the primary care teams from the city of Barcelona referral rate.