1. Folic acid food fortification to prevent neural tube defects
Nicholas J Wald, Malcolm Law, Rachel Jordan 
The Lancet 
Volume 351, Issue 9105, (March 1998)
DOI: /S (05)
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2. Figure Neural tube defect (NTD) prevalance per 1000 births
Bars=95% confidence intervals in relation to red cell folate. Adapted from Daly and colleagues.1
The Lancet  , DOI: ( /S (05) )
Copyright © 1998 Elsevier Ltd Terms and Conditions