https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-11-55 https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-11-54 https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-11-56 https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-11-53 https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-11-57 https://ehjournal.biomedcentral.com/articles/10.1186/1476-069X-11-52