Before revision: It aimed to enroll 20,000 participants (women 55 or over, men 50 or over) who will be randomized to one of four groups:VITAL Study daily vitamin D (2000 IU) and fish oil (1 g); daily vitamin D and fish-oil placebo; daily vitamin-D placebo and fish oil; daily vitamin-D placebo and fish-oil placebo.
After revision: It aimed to enroll 20,000 participants (women 55 or over, men 50 or over) who were randomized into one of four groups:VITAL Study daily vitamin D (2000 IU) and fish oil (1 g); daily vitamin D and fish-oil placebo; daily vitamin-D placebo and fish oil; daily vitamin-D placebo and fish-oil placebo.