Media type: Electronic Journal Title: BMJ open Published: London: BMJ Publishing Group, 2011- Publication information: 2011 - Language: English ISSN: 2044-6055 Keywords: Zeitschrift Origination: Footnote: Access State: Open Access Rights information: Attribution - Non Commercial (CC BY-NC) Attribution (CC BY) Attribution - Non Commercial - No Derivs (CC BY-NC-ND)