treated at safety-net urban hospitals. Some evidence also suggests that minority patients are more likely than whites to be treated by less proficient physicians (Mukamel et al., 2000).
One factor that needs to be more consistently taken into account in studying racial and ethnic differences is the role of geography or residential area. Access to high-quality care varies considerably by area—by state, between rural and urban areas, as well as across smaller communities (Waidmann and Rajan, 2000; Wennberg and Cooper, 1999). Since racial and ethnic groups are unevenly distributed across communities, geographic variation in health care has the potential to explain some health care differences. For instance, states with large proportions of blacks tend to provide less appropriate treatment to all myocardial infarction patients, whether black or not, than states with smaller proportions of blacks (Chandra and Skinner, 2004).
The relationship between geographic variation and racial and ethnic differences in health care is complex. Some geographic variation may be due to racial factors related to residential segregation by race. But some variation in care is clearly not geographic, as when variations exist within geographic areas. Several studies have found racial and ethnic differences in care in a single facility (e.g., Baker et al., 1996; Chung et al., 1995; Lowe et al., 2001; Moore et al., 1994; Ng et al., 1996; Peterson et al., 1997; Todd et al., 1993, 2000); a single geographic location (Herholz et al., 1996; Ramsey et al., 1997; Segal et al., 1996); and, in the case of cardiovascular disease, even after a broad range of hospital characteristics are considered (Geiger, 2002).
Health care can also vary within health systems, though some studies show similar treatment for different racial groups. In the Veterans Administration health system, for instance (where differences in insurance coverage are minimized), black-white differences do not appear for the treatment of colorectal cancer (Dominitz et al., 1998) but have been shown in the treatment of heart disease (Oddone et al., 1998; Peterson et al., 1994; Sedlis et al., 1997; Whittle et al., 1993), gall-bladder disease (Arozullah et al., 1999), and mental health (Kales et al., 2000). In Department of Defense medical facilities, no black-white differences were found in the treatment of prostate cancer (Optenberg et al., 1995) or cervical cancer (Farley et al., 2001). Similarly, no differences were found in treatment of acute myocardial infarction through catheterization and revascularization procedures, but whites were more likely than minorities to be considered for future catheterization (Taylor et al., 1997).