Self-Reported Use of Mammography Among Women ³ 40 Years Old

In 1997, breast cancer will be diagnosed in an estimated 180,200 women, and 43,900 women will die from the disease. Early detection combined with timely and appropriate treatment can alter the progress of and reduce mortality from this disease. Effective screening procedures are available to detect breast cancer in its early stages. However, the benefits of breast cancer screening to reduce mortality in the population can be achieved only if screening guidelines are followed and a large proportion of women receive screening examinations regularly. To estimate the state-specific proportions of women ³ 40 years old who reported receiving a mammogram during the preceding 2 years, The Centers for Disease Control (CDC) analyzed data from the Behavioral Risk Factor Surveillance System for 1989 and 1995. This report presents the findings, which indicate that, from 1989 to 1995, the percentage of women age ³ 40 years who reported receiving a mammogram during the preceding 2 years increased in all 39 states in the survey.

In 1989 and in 1995, a total of 39 states participated in the Behavioral Risk Factor Surveillance System. Using a multistage sampling design and a random-digit-dialed telephone survey, each state conducted monthly telephone interviews of a random sample of its noninstitutionalized adult (age more than18 years) population to provide state-specific estimates of risk factors and the use of preventive services. Annual data are weighted to the age, sex, and race distribution of each state’s adult population using the most current census or intercensal estimates. Three Behavioral Risk Factor Surveillance System questions focused on mammography use and were asked only of female respondents ³ 40 years old. Each respondent was asked, “Have you ever had a mammogram?” If the respondent answered “yes” to that question, she was asked, “How long has it been since your last mammogram?” and “Was it part of a routine checkup, because of a breast problem other than cancer, or because you had already had breast cancer?” In this analysis, estimates are age-adjusted to the age distribution of women in the 1989 Behavioral Risk Factor Surveillance System sample for participating states.

From 1989 to 1995, the overall age-adjusted proportion of women age ³ 40 years who reported having had a mammogram during the preceding 2 years increased in each of the 39 participating states (Table 1). The age-adjusted proportion varied widely among the states, from 43.8% to 65.2% in 1989 to 63.0% to 79.7% in 1995. The median age-adjusted proportion was 53.3% in 1989 and 69.5% in 1995. During this period, the state-specific relative percentage increase ranged from 9% in Minnesota (which, in 1989, already had a relatively high proportion of women who reported having had their most recent mammogram during the preceding 2 years) to approximately 45% in West Virginia and New York.

Editorial Note from the CDC

Mammography is the primary procedure for breast cancer screening. The US Preventive Services Task Force recommends a screening mammogram every 1 to 2 years for women 50 to 69 years old. In addition, physicians can recommend that high-risk women aged less than 50 years receive a screening mammogram. The National Cancer Institute’s 1997 mammography guidelines recommend screening mammograms every 1 to 2 years for women age ³ 40 years if they are at average risk for breast cancer. Recently revised American Cancer Society guidelines recommend annual mammography for women age ³ 40 years.

The findings in this report indicate that, from 1989 to 1995, the percentage of women age ³ 40 years who reported having had a mammogram during the preceding 2 years increased in all 39 states participating in the Behavioral Risk Factor Surveillance System. This finding is consistent with previous studies that indicated increasing reported use of screening mammograms. For example, based on data from the National Health Interview surveys, of women age ³ 40 years in 1987, 29% reported having had a mammogram during the preceding 2 years; in 1994, the proportion increased to 61%. Similarly, the proportion of women who reported receiving breast cancer screening consistent with American Cancer Society guidelines increased from 31% in 1990 to 47% in 1995.

The findings in this report are subject to at least four limitations. First, only 39 states participated in both the 1989 and 1995 Behavioral Risk Factor Surveillance Systems; therefore, the results may not be generalizable to the total US population of women age ³ 40 years. Second, the telephone survey excluded women living in households without a telephone. Although only 5% of US households are without telephones, the proportion of persons without telephones varies by geographic region, and the characteristics of households with and without telephones are different. Thus, the differences observed in this survey may not reflect trends for women without telephones. Third, self-reported mammography use may not be consistent with reports of mammography use from other sources, such as medical and imaging-center records. Finally, because approximately 15% to 20% of contacted households did not respond and respondents may be different from nonrespondents, the precision of the estimates in this report may be reduced.

Regular breast cancer screening can reduce the annual rate of breast cancer deaths in the United States; the estimated potential reduction ranges from 19% to 30% for women 50 to 74 years old. Federal initiatives, such as the CDC’s National Breast and Cervical Cancer Early Detection Program and Medicare, encourage breast cancer screening by paying for mammograms for women eligible to participate in these programs. Since 1991, Medicare has provided insurance coverage for biannual mammograms. National Breast and Cervical Cancer Early Detection Program provides states, US territories, and programs serving American Indians/Alaskan Natives with resources to provide screening, follow-up, and referral services to medically underserved women. National Breast and Cervical Cancer Early Detection Program outreach efforts are aimed at older women, women with low incomes, uninsured or underinsured women, and women of racial/ethnic minority groups. Initiatives to encourage women to receive an initial screening for breast cancer are essential and should emphasize re-screening.