Why search for congenital defects?

The causation of congenital malformation is receiving increased study. In Canada, epidemiologic surveys are being planned, based upon the institution of Provincial Registries to which physicians and other agencies will voluntarily report cases coming to their attention. The literature in regard to prevalence studies of congenital cardiac defects in school children is reviewed. Over the past 25 years, studies employing the proposed technique demonstrated a rising trend, from 1.4 per 1000 to 2.6 per 1000. By contrast, specific surveys for congenital cardiac defect carried out by expert personnel using radiographs and electrocardiographs, resulted in essentially uniform rates, approximating 5 to 6 per 1000. It is concluded that the latter is a superior technique of epidemiologic survey over the "Central Registry" method, and should command a due proportion of health resources directed towards congenital malformation research.