| Citation | Professor Nicholas Wald is distinguished for major advances in epidemiology and preventive medicine in several areas. His work on alphafetoprotein screening for neural tube defects has been the basis for screening for these disorders over the last 20 years and has included a novvel quantitative method, mutiples of the median or MoMs, for enabling valid comparisons of results within and between different laboratories. This methid has had important general applicability in other conditions. He designed and conducted the multinational randomised trial showing that folic acid supplements before and during pregnancy lead to a reduction of 72% in the risk of neural tube defects. Through screening improvements and folic acid consumption, neural tube defects are now rarely seen in the UK. He has also been a world leader in antenala screening for Down's syndrome witht eh development of the triple test in 1988 and subsequent related advances. He has described and piloted an ingenious method of antenatal screening for cystic fibrosis couple screening. His work on cigarette smoking quantifies and clarifies the lower degree of hazard associated with reduced tar cigarettes and pipe smoking, and the hazards of passive smoking. In studies of the aetiology of cardiovascular disease, he has demonstrated the quantitative contributions of salt, serum cholesterol, apoliproteins and homocysteine, as well as excluding an effect of H pylori infection. |