Figure 1
From: The influence of early exposure to vitamin D for development of diseases later in life
Study cohorts. The figure provides examples of designs for examining the effects of vitamin D fortification on development of diseases for a follow-up period of up to 50ὕyears. The birth (grey boxes with allowance for short “wash-out period” in between) and follow-up years (arrows) of individuals from subgroups exposed before and after birth are given in relation to initiation or termination of vitamin D fortification.