https://joppp.biomedcentral.com/articles/10.1186/s40545-016-0079-1
https://joppp.biomedcentral.com/articles/10.1186/s40545-016-0081-7
https://joppp.biomedcentral.com/articles/10.1186/s40545-016-0080-8
https://joppp.biomedcentral.com/articles/10.1186/s40545-016-0076-4
https://joppp.biomedcentral.com/articles/10.1186/s40545-016-0077-3
https://joppp.biomedcentral.com/articles/10.1186/s40545-016-0075-5