https://pophealthmetrics.biomedcentral.com/articles/10.1186/s12963-020-00233-0
https://pophealthmetrics.biomedcentral.com/articles/10.1186/s12963-020-00234-z
https://pophealthmetrics.biomedcentral.com/articles/10.1186/s12963-020-00235-y
https://pophealthmetrics.biomedcentral.com/articles/10.1186/s12963-020-00236-x