1. Department of Obstetrics and Gynaecology; Faculty of Medicine, Khon Kaen University; Khon Kaen Thailand
2. Department of Obstetrics and Gynaecology, Faculty of Medicine; Khon Kaen University; Khon Kaen Thailand
3. Cochrane Thailand; Khon Kaen University; Khon Kaen Thailand
4. Geneva Switzerland
5. Obstetrics and Gynaecology; Faculty of Medicine, Khon Kaen University; Khon Kaen Thailand