Text and Data Mining valid from 2018-05-02
First Online: 2 May 2018
Ethics approval and consent to participate
: This study was approved by the Ethics Committee of St. Marianna University School of Medicine. The reference number is 3305.
: Since this study was conducted under a retrospective cohort design without any samples taken besides those for clinical use, written informed consent was not acquired, in accordance with the guideline of Ministry of Health, Labour and Welfare of Japan.
: The authors declare that they have no competing interests.
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