1. School of Nursing and Health Zhengzhou University Zhengzhou China
2. WHO Collaborating Center for Community Health Services, School of Nursing The Hong Kong Polytechnic University Hung Hom, Kowloon Hong Kong SAR China
3. School of Nursing The Hong Kong Polytechnic University Hung Hom, Kowloon Hong Kong SAR China
4. School of Nursing Johns Hopkins University Baltimore Maryland USA