https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-2
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-5
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-4
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-6
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-1
https://health-policy-systems.biomedcentral.com/articles/10.1186/1478-4505-9-3