A team of researchers conducted a prospective cohort study t…
A team of researchers conducted a prospective cohort study to determine if children who are born to mothers who took folic acid during pregnancy are less likely to develop leukemia. The average age at which childhood leukemia is diagnosed is about 2 years old. To ensure that sufficient time has elapsed for leukemia to be initiated and to become clinically detectable, the researchers decided to follow the children until age 3. What period did the researchers consider when determining the length of follow-up?