1. School of Social and Community Medicine, University of Bristol, Bristol, BS10 5NB, England.
2. Mpilo Central Hospital, Bulawayo, Zimbabwe.
3. School of Clinical & Experimental Medicine, Birmingham Women's Hospital Foundation Trust, Birmingham, England.
4. Morriston Hospital, Swansea, Wales.
5. Royal Glamorgan Hospital, Cardiff, Wales.
6. Bay of Plenty District Health Board, Whakatane Hospital, Whakatane, New Zealand.