1 School of Nursing, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong SAR, People's Republic of China. cyklau@connect.hku.hk.
2 Jockey Club School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, People's Republic of China. cyklau@connect.hku.hk.
3 School of Nursing, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong SAR, People's Republic of China.
4 Faculty of Social Science, The Chinese University of Hong Kong, Hong Kong SAR, People's Republic of China.
5 Department of Obstetrics and Gynecology, Princess Margaret Hospital, Hong Kong SAR, People's Republic of China.
6 Registered Midwife, Hong Kong SAR, People's Republic of China.
7 Department of Obstetrics and Gynecology, Kwong Wah Hospital, Hong Kong SAR, People's Republic of China.
8 Maternity, Matilda International Hospital, Hong Kong SAR, People's Republic of China.
9 School of Nursing, Okanagan Campus, University of British Columbia, Kelowna, Canada.