Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
| Blood group | NHS (%) | HPFS (%) | Total study population (%) |
| O | 42.9 | 42.7 | 42.8 |
| A | 36.0 | 37.9 | 36.5 |
| AB | 7.8 | 7.4 | 7.7 |
| B | 13.3 | 12.0 | 12.9 |
| Rh negative | 22.6 | 21.4 | 22.3 |
| Rh positive | 77.4 | 78.6 | 77.7 |
NHS = Nurses' Health Study, HPFS = Health Professionals Follow-up Study.
