2.3. Subject Recruitment
RECRUITMENT
Participants were recruited via a mass email invitation delivered to the eligible subjects via collaborators in the Hong Kong Polytechnic University (HKPU) and University of Hong Kong (HKU). A QR code flyer embedded with an electronic application form was flagged up in all communal areas in HKPU and HKU campus. The recruitment period spanned for three months from 1 August to 31 October 2021.