Although screening programs for neural tube defects (NTDs) are routine and cost-effective in Great Britain their potential use in the United States has been hotly debated. In this chapter we report the attitudes of 338 prospective patients seeking genetic counseling about the use of amniocentesis for prenatal diagnosis. We have integrated these attitudes with the expected accuracy and complications of a comprehensive screening program for NTDs and have estimated the proportion of these prospective parents who would benefit from a maternal serum alpha-fetoprotein (AFP) screening program. Thus, we have addressed perhaps the most critical problem related to the decision of whether or not to institute an AFP screening program: “What are the implications of the attitudes of prospective parents toward the desirability of a large-scale screening program for the prenatal detection of NTDs?” In a larger sense, we are addressing a prototypical problem for many policy analyses: How can the personal attitudes of individual members of society be integrated into decisions affecting the medical care of society as a whole?

METHODS

Summary of screening plan. Figure 28.1 summarizes the policies analyzed in this paper. Maternal serum AFP concentration is measured at a gestational age between 16 and 18 weeks. If the concentration of AFP is above a predetermined level (typically either 2.5 times the median or two standard deviations above the mean), the serum test is repeated.