Methodological issues in newborn screening evaluation with special reference to congenital adrenal hyperplasia

Evidence-based evaluation of newborn screening is essential because of the increasing number of genetic tests, the mandatory nature of newborn screening in the United States, and the growing cost to the public to maintain expensive screening programs. This paper discusses the methodological problems that arise when applying universally accepted criteria to disorders such as congenital adrenal hyperplasia. These problems include the tendency of screening to alter the natural history of the disease, the lack of consensus about terms and definitions, and the paucity of longitudinal studies on screen detected neonates. In order to evaluate and compare candidate screens we recommend formal national trials of promising programs, with defined responsibility of state agencies, physicians, patients, and insurers for data submission and analysis.