Funding for this research was provided by:
Chang Gung Memorial Research Grant (CMRPG890891)
Received: 1 January 2019
Accepted: 3 July 2019
First Online: 24 July 2019
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board of Chang Gung Memorial Hospital, under Protocol number 99-0948A3. All participants gave their informed written consent to take part in the study.
: Not applicable.
: The authors declare that they have no competing interests.