https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-11
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-7
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-9
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-8
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-10