Retraction
This article has been retracted [1] by the authors because they do not have ownership of the data presented, which was originally collected by the Laboratorio Management e Sanità of Scuola Superiore Sant’Anna. In addition, the data presented in this article has previously been used for a publication in the Italian journal “Mercati e Competitività” [2]. The authors apologise to the readers, the publisher and the authors of the Italian publication for any inconvenience caused.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.