Funding for this research was provided by:
Hong Kong Council on Smoking and Health
Received: 8 May 2020
Accepted: 26 January 2021
First Online: 6 February 2021
Ethics approval and consent to participate
: Due to the nature of the lane-line telephone survey, participants only provided oral consent before being able to take part in this study and we obtained oral consents from parent or guardian of participants under 16 years old. The oral consent and ethical approval have been approved by the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster (Ref: UW15–108).
: Not applicable.
: MPW is one of the associate editors of health behavior, health promotion and society of BMC Public Health journal.