Funding for this research was provided by:
Portuguese Neonatal Society ("Milupa 2011")
Text and Data Mining valid from 2018-09-17
Received: 27 March 2018
Accepted: 27 August 2018
First Online: 17 September 2018
Ethics approval and consent to participate
: Parents or guardians of all infants gave their informed consent before inclusion in the study, and the study was conducted in accordance with the tenets of the Declaration of Helsinki.
: Not applicable.
: The authors declare no conflict of interest. The funding sponsors had no role in the design of the study, in the collection, analyses, or interpretation of data, in the writing of the manuscript and in the decision to publish the findings.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.