Yao, Yao
Article History
Received: 13 April 2018
Accepted: 13 November 2018
First Online: 20 December 2018
Ethics approval and consent to participate
: The study was approved by the Human Subjects Ethics Application Review System at the Hong Kong Polytechnic University (no. HSEARS20130406001-02), and written consent was obtained from all the participants.
: Not applicable.
: The author declares that there are no competing interests.
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