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.
Relative risk (fixed) and 95% confidence intervals for prostate cancer vs. controls associated with vitamin E alone or with other supplements. Test for heterogeneity: χ2=5.70; df=3 (P=0.13), F=47.4%. Test for overall effect: Z=2.50 (P=0.01).
