A review of the literature was performed electronically in PubMed (PubMed Central, and MEDLINE) for articles published in English from 2000 to April of 2017. 
PubMed
A review of the literature was performed electronically in PubMed (PubMed Central, and MEDLINE) for articles published in English from 2000 to April of 2017. 
PubMed Central
A review of the literature was performed electronically in PubMed (PubMed Central, and MEDLINE) for articles published in English from 2000 to April of 2017. 
MEDLINE