Funding for this research was provided by:
Instituto de Salud Carlos III (PI15/01230)
Received: 18 December 2017
Accepted: 16 April 2018
First Online: 27 April 2018
Ethics approval and consent to participate
: The study was approved by the ethical committee of the Institution (ethic committee IDIAP Jordi Gol P14/134) and was conducted in accordance with the general principles for observational studies. Given this is a non-interventional study, an informed consent for all 2,025,730 study participants was formally waived by the ethics committee and was not required. Data were anonymized and risk of identification was null.
: The authors declare that they have no competing interests.
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