Received: 19 April 2018
Accepted: 10 January 2019
First Online: 28 January 2019
Ethics approval and consent to participate
: This was a retrospective study carried out using hospital claims data from the Medical Data Vision® database; the authors were not involved in the collection of these data. Patients were informed that their data would be used for research purposes (opt-out system) and their data were de-identified before entry into the research database. Retrieval of the data from this database occurred in an unlinked fashion. As the data had been anonymized, the Ethical Guidelines for Epidemiological Research (Ministry of Education, Culture, Sports, Science and Technology, and Ministry of Health, Labour and Welfare of Japan), which require ethics approval and informed consent, are not applicable to this study. Based on the Ethical Guidelines on Biomedical Research Involving Human Subjects (Ministry of Education, Culture, Sports, Science and Technology, and Ministry of Health, Labour and Welfare of Japan), pharmacoepidemiological studies conducted on medical databases constitute research carried out on pre-existing material and information that does not require any intervention or interaction with patients. For such studies, including this study, obtaining written informed consent from patients is not mandatory.
: Not applicable.
: JM and RS were employed at Janssen KK Japan at the time the study was conducted.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.