data that shed light on quality of care. Some of these were identified through our search, but it is likely that many others were not.
We divided our review of quality in the United States into three categories: underuse (Table A-1), overuse (Table A-2), and misuse (Table A-3). Underuse indicates that a health care service for which the potential benefits outweigh the potential risks (i.e., necessary care) is not provided. Overuse indicates the reverse—a health care service is provided when the potential risks outweigh the potential benefits (i.e., inappropriate care). Misuse occurs when otherwise appropriate care is provided in a way that leads to or could lead to avoidable complications. Examples of misuse include when an antibiotic appropriate to the patient’s infection is prescribed despite the fact that the patient has a documented allergy to the antibiotic, or when two drugs, each of which is appropriate for a patient’s condition, are prescribed despite contraindications to prescribing them together. An incorrect dose or dosing schedule is also considered misuse.
In each summary table, we list (and sometimes describe) the health care service for which quality is reported, the sample on which the report is based, the data source for the sample, the findings, and the reference. The tables report data from 73 articles.
Perhaps the most striking revelation to emerge from this review is the surprisingly small amount of systematic knowledge available on the quality of health care delivered in the United States. Even though health care is a huge industry that affects the lives of most Americans, we have only snapshots of information about particular conditions, types of surgery, and locations of care.
The dominant finding of our review is that there are large gaps between the care people should receive and the care they do receive. This is true for preventive, acute, and chronic care, whether one goes for a checkup, a sore throat, or diabetic care. It is true whether one looks at overuse, underuse, or misuse. It is true in different types of health care facilities and for different types of health insurance. It is true for all age groups, from children to the elderly. And it is true whether one is looking at the whole country or a single city.
A few examples emphasize this point. An annual influenza vaccine is recommended as a preventive measure for all adults 65 years or older, a group at especially high risk for complications and death from influenza (U.S. Preventive Services Task Force, 1989, 1996). However, in 1993, only 52 percent of people in this age group in the United States received the vaccine; among people who had been to the doctor at least once that year, the percentage was slightly higher at 56 percent (Centers for Disease Control and Prevention, 1995b).