Received: 17 February 2017
Accepted: 6 March 2018
First Online: 22 March 2018
Ethics approval and consent to participate
: The CCR-OSHPD linked data sets are available only to health care researchers and their affiliated institutions. Research proposals require both California state and institutional-level human subjects review. Accordingly, this study was approved by the California Committee for the Protection of Human Subjects (CPHS), and by the Institutional Review Board of City of Hope Medical Center. The approvals have been renewed annually and are both currently active.
: Not applicable.
: The authors declare that they have no competing interests.
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