to prove to be complex when integrating other factors such as psychological responses to illness. Exposure to psychological stresses and a lack of coping skills or resources also affect survival from cancer. Individuals of lower SES are less likely to have social networks and support than those of higher SES, because the former may lack employment or other social resources in their communities. Such social supports contribute to a sense of connection to others, aiding in one's ability to deal with an illness such as cancer (Harvard Center for Cancer Prevention, 1996). Increased research support in this area may demonstrate that strengthening social support for those with cancer in disadvantaged communities can help to lower mortality rates when the many components of lower SES prove less amenable to intervention.
In summary, poverty "is a proxy for other elements of living, including lack of education, unemployment, substandard housing, poor nutrition, risk-promoting lifestyle and behavior, and diminished access to health care" (Freeman, 1990, p. 18), all of which affect an individual's chances of developing cancer and surviving it.
NCI does not define SES in its report to this committee (National Cancer Institute, 1998b), although it does consider individuals of low income as "special populations," without further defining that group. Nevertheless, studies are underway at NCI to evaluate the extent to which racial and ethnic disparities in cancer incidence may be related to SES factors (see Chapter 3). As noted above, however, the term "low SES" could imply the existence of a number of cancer risk factors, yet for the low-income group within the NCI's "special populations" portfolio the focus seems to be only on the lack of monetary resources. It is therefore unclear what populations are referred to, or what needs should be addressed first (i.e., education, income, insurance status, or social environment) to reduce the risk of cancer.
Unfortunately, differences in SES among U.S. ethnic groups exist. When examined collectively, African Americans and Hispanics are three times as likely as whites to be poor, according to U.S. Census Bureau (as reported by the National Center for Health Statistics, 1998; see Table 2-2). Such gaps have been related to inequalities in the levels of educational and economic attainment associated with racial barriers (Gimenez, 1989; Lillie-Blanton and LaVeist, 1996; Harvard Center for Cancer Prevention, 1996). Low SES and ethnic minority status are not synonymous, but many members of ethnic minority groups who also have low income comprise an important proportion of underserved populations in the United States. Low-income ethnic minorities are least likely to have a regular source of