We outline the implementation of a new method of measuring the quality of medical care that counts cases of unnecessary disease and disability and unnecessary untimely deaths. First of all, conditions are listed in which the occurrence of a single case of disease or disability or a single untimely death would justify asking, "Why did it happen?" Secondly, we have selected conditions in which critical increases in rates of disease, disability, or untimely death could serve as indexes of the quality of care. Finally, broad categories of illness are noted in which redefinition and intensive study might reveal characteristics that could serve as indexes of health. We describe how these inth of the general population and the effects of economic, political, and other environmental factors upon it, and to evaluate the quality of medical care provided both within and without the hospital to maintain health and to prevent and treat disease.

Congestive heart failure is a common problem in the U.S., with significant prevalence and mortality, both of which increase with advancing age. As the population of the U.S. becomes older, the health care impact of congestive heart failure will probably grow.

Aplastic anemia has been linked to environmental exposures, from chemicals and medical drugs to infectious agents. The disease occurs more frequently in Asia than in the West, with incidence rates 2-to 3-fold higher. We report updated results of an epidemiologic study conducted in Thailand from 1989 to 2002, in which 541 patients and 2261 controls were enrolled. Exposures were determined by in-person interview. We observed significantly elevated relative risk estimates for benzene (3.5) and other solvents (2.0) and for sulfonamides (5.6), thiazides (3.8), and mebendazole (3.0). Chloramphenicol use was infrequent, and no significant association was observed. Agricultural pesticides were implicated in Khonkaen (northeastern Thailand). There were significant associations with organophosphates (2.1), DDT (6.7), and carbamates (7.4). We found significant risks for farmers exposed to ducks and geese (3.7) and a borderline association with animal fertilizer (2.1). There was a significant association in Khonkaen with drinking other than bottled or distilled water (2.8).