Self-Reported Use of Mammography and Insurance Status Among US Women Over the Age of 39, From 1991 to 1992 and 1996 to 1997

In the United States, breast cancer is the most commonly diagnosed malignancy among women and the second leading cause of cancer death. Lack of health insurance coverage often is an important financial barrier to seeking preventive health care, such as mammography screenings. To assess mammography use and the impact of insurance status on mammography use, state-specific proportions of women age ³ 40 years who reported receiving a mammogram during the preceding 2 years by insurance status were derived using data from the Behavioral Risk Factor Surveillance System (BRFSS) for 1991 to 1992, and 1996 to 1997. This report describes the results of this analysis, which indicate that the percentage of women reporting having had a screening mammogram during the previous 2 years increased, but women with insurance were substantially more likely than women without insurance to have had a mammogram.

Forty-six states and the District of Columbia (DC) participated in BRFSS surveys during 1991 to 1992, and 1996 to 1997.a Using a multistage sampling design and random-digit dialing, each state conducted monthly telephone interviews sampling noninstitutionalized adults (age ³ 18 years). Annual data were weighted to the age, sex, and race distribution of each state’s adult population using 1994 census or intercensal estimates. Female respondents age ³ 40 years were asked, “Have you ever had a mammogram?” If the respondent answered “yes,” she was asked, “How long has it been since your last mammogram?” and “Was it part of a routine check-up, or was it because of a breast problem other than cancer, or was it because you had already had breast cancer?” Respondents also were asked, “Do you have any kind of health care coverage, including health insurance, prepaid plans such as HMOs, or government plans such as Medicare?” In the 1996 and 1997 surveys, respondents who answered “no” were asked to reconsider the question. For consistency between the surveys, this analysis categorized respondents in 1996 and 1997 who first answered “no” to the insurance question as uninsured, even if they answered “yes” when asked again; the increase in the percentage of persons insured based on “yes” responses on reconsideration of the question was < 2%.

Almost all women age ³ 65 years have Medicare coverage. However, the aggregated results for all women age ³ 40 years are presented because this format is consistent with prior analyses of trends in mammography coverage using data from the BRFSS and national objectives for breast cancer screening. To compensate for the potential effects of the resulting differences in age distributions between insured and uninsured women, estimates were age-adjusted to the age distribution of women in the 1994 BRFSS sample for participating states.

Results

The overall pooled age-adjusted proportion of women with insurance who reported having had a mammogram was 65.2% in 1991 to 1992 and 70.9% in 1996 to 1997; the proportion of women without insurance who reported having had a mammogram was 39.6% in 1991 to 1992 and 46.2% in 1996 to 1997. In each of the 46 states and DC in both 1991 to 1992 and 1996 to 1997, the prevalence of self-reported screening mammography use within the previous 2 years was higher among insured women than among uninsured women; uninsured women represented approximately 9% of the sample in 1996 to 1997.

Among insured women, from 1991 to 1992 and 1996 to 1997, the age-adjusted proportion age ³ 40 years who reported having had a mammogram during the preceding 2 years increased in 43 states. Increases in 26 states were statistically significant; the largest absolute increases in mammography use were in Mississippi (from 51.4% to 65.3%) and Alaska (from 63.9% to 76.4%). Mammography use decreased in three states (Minnesota, Vermont, and Washington) and DC, but the changes were not statistically significant.

Among uninsured women, mammography use increased in 33 states; the increase was significant in six. The largest absolute increases were 31.0% in Alaska (from 33.8% to 64.8%) and 23.9% in New Jersey (from 23.7% to 47.6%). Although there were decreases in 14 states, the only statistically significant decrease was in New Hampshire (from 51.1% to 32.4%; P = .047).

Editorial Note From the CDC

The findings in this report indicate that the percentage of women reporting having had a screening mammogram in the previous 2 years has increased over time, and this increase has been observed among both insured and uninsured women. However, women without insurance continue to be substantially less likely than women with insurance to have this procedure. These results underscore the importance of public health activities to increase access to breast and cervical cancer screening services for women who are medically underserved. If breast cancer mortality is to continue to decrease, then access to mammography for all women, particularly the uninsured, must be enhanced.

The findings in this report are subject to at least three limitations. First, because the BRFSS is a telephone survey, women living in a household without a telephone (5% of US households) are excluded. Second, the survey’s self-reported data may not be consistent with reports of mammography use from medical records. However, studies comparing self-reports with medical records found that the error in self-reporting mammography use is not substantial enough to explain the differences seen in the analyses described in this report. Finally, the response rates within the BRFSS have dropped from 84.1% and 82.9% in 1991 and 1992, respectively, to 77.9% and 76.8% in 1996 and 1997, respectively. Because respondents may differ from nonrespondents, this increase in nonresponse could portend greater bias in later samples.

This study indicates that lack of health insurance decreases the likelihood that a woman will receive a mammogram. This is an important finding given the efforts being made to reduce breast cancer mortality in this country, where a substantial proportion of women lack health insurance. The demonstrated efficacy of regular breast cancer screening with mammography suggests that efforts such as CDC’s National Breast and Cervical Cancer Early Detection Program, a comprehensive nationwide program administered through state health departments and American Indian/Alaskan Native tribal organizations, could facilitate the early detection of breast cancer in underserved women.