https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-7-9
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-7-13
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-7-10
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-7-12
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-7-11