Why does αlpha not draw attention to markers which are individually high or low?
αlpha takes into consideration all the measured screening markers when calculating the Down’s syndrome risk estimate since this provides the most accurate determination of risk. While it is known that very high or very low levels of the individual screening markers can be associated with adverse outcomes of pregnancy, such as miscarriage or still birth, the predictive screening performance is usually poor, and there is, in most cases no remedy. It is accepted that it is poor medical and screening practice to look for disorders for which there is no remedy.