Funding for this research was provided by:
Princess Margaret Hospital Respiratory Fund (ID0EAHBG4377)
Text and Data Mining valid from 2019-03-15
Received: 23 February 2018
Accepted: 27 February 2019
First Online: 15 March 2019
Ethics approval and consent to participate
: The study protocol was approved by the Kowloon West Cluster Research Ethics Committee, Hospital Authority of Hong Kong, followed the principles of the Declaration of Helsinki. All participants provided written informed consent for data collection.
: Not applicable.
: The authors declare that they have no competing interests.
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