Received: 8 November 2018
Accepted: 3 January 2019
First Online: 22 January 2019
Ethics approval and consent to participate
: The protocol was approved by the investigational review board at Baqiyatallah University of Medical Sciences (IR.BMSU.REC.1394.441), which was accepted by each of the participating medical centers: Baqiyatallah Hospital, Shariati Hospital, Masih Daneshvari Hospital, Loghman Hakim Hospital, Shahid Madani Hospital, Ghaem Hospital, Besat Hospital, and Rouhani Hospital. Consent was required and covered both study participation and publication of findings. Informed consent was required prior to cardiac arrest event and could be provided by the patient, legal guardian, or healthcare surrogate.
: The informed consent included permission to present and publish de-identified results.
: The authors declare that they have no competing interests.
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