1. School of Medical and Health Sciences, Edith Cowan University, Perth, Australia;
2. Department of Molecular Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana;
3. Department of Obstetrics and Gynaecology, Komfo Anokye Teaching Hospital, Kumasi, Ghana;
4. Beijing Key Laboratory of Clinical Epidemiology, School of Public Health, Capital Medical University, Beijing, China;
5. School of Public Health, Taishan Medical University, Taian, China