The four studies
| Study No | Location, and year | Patient setting | Diagnostic test used | Number of patients with full risk information |
|---|---|---|---|---|
| 1 | London, 1992 | Blood donors | Modified western blot | 1359 |
| 2 | London, 1990–2 | STI clinic attendees | Modified western blot | 808 |
| 3 | Sydney, 1995–8 | Women, antenatal care | Type specific ELISA | 2317 |
| 4 | Seattle, 1991–3 | Family medical centre | Western blot | 476 |