Received: 18 July 2018
Accepted: 15 February 2019
First Online: 26 February 2019
Ethics approval and consent to participate
: This ecological study was submitted to a local Research Ethics Committee (REC), according to Resolution no 466/12 of December 12th, 2012, from the National Health Council and complementary resolutions (240/97, 251/97, 292/99, 303/2000, 304/2000, 340/2004, 346/2005 and 441/2011). However, as it comes to secondary data from public databases, this study was exempted from consideration by the REC, according to REC Office 009/2016.
: Not applicable.
: The authors declare that they have no competing interests.
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