Strategies in underwriting the costs of catastrophic disease.

"Catastrophic" illness has recently been recognized as a major problem of public policy. Diseases may be considered "catastrophic" for policy purposes simply because of their calamitous nature or because of their high treatment costs. Early steps extending protection against catastrophic illness were confined to identifying specific diseases as catastrophic so as to concentrate governmental efforts on a limited class of patients;' the advantage of this categorical approach was the greater control that it provided over the government's financial commitment, which could be gradually expanded as political pressures built on behalf of new diseases and as resources became available. Now, however, concern about catastrophic illness seems to be focused not on specific diseases but on the general hazard of financial disaster associated with high health care costs. A patient's disease is considered catastrophic in this sense only if it is extraordinarily expensive to treat. Thus, contrary to popular