Received: 10 July 2017
Accepted: 22 February 2018
First Online: 11 April 2018
Ethics approval and consent to participate
: The study protocol was approved at the ethical committee at Chiba University Graduate School of Medicine, as an epidemiological study conducted on residual patient blood samples. Written consent for enrollment was obtained from patients and/or their legal representatives as an agreement at ICU admission for the extended use of residual serum samples obtained for usual clinical practice. Patients and/or their legal representatives were informed about the details of the study by a documented explanation form and were given the right to withdraw consent after enrollment.
: The authors declare that they have no competing interests.
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