Received: 8 January 2018
Accepted: 8 May 2018
First Online: 25 May 2018
Ethics approval and consent to participate
: The study was not submitted to an ethic commission as only anonym routine data of an insurance were used and no personal data were collected and no medical test was performed in the scope of the study. In accordance with the Professional Code for Physicians in Hamburg (Art. 15, 1., Status of 10.03.2014) and the Chamber Legislation for Medical Professions in the Federal State of Hamburg (HmbKGH) it is only necessary to obtain advice on questions of professional ethics and professional conduct from an Ethics Committee if data which can be traced to a particular individual is being used in a research project. However, the study was approved by the data protection board of the insurance which provided the data.
: The authors declare that they have no competing interests.
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