Raleigh, N.C. — Elizabeth Edwards, who died Tuesday after a six-year battle with breast cancer, gave powerful testimony about the need for early detection of the disease.

In what was perhaps her last public appearance, Edwards said she neglected to get annual exams.

"I did not take advantage of the tests we knew we had for breast cancer," she said at Cleary University in Michigan in October. "Like many women, I made sure my children had their annual check-ups, and I did not have mine."

Edwards' experience is not uncommon among women who are the age she was when she was diagnosed in 2004, research shows.

The most recent data from the Centers for Disease Control and Prevention shows that only 79.9 percent of women ages 50 to 59 had up-to-date mammography tests.

Among people who did not finish high school, 72.6 percent received recommended screening. For those with an annual income of less than $15,000, 69.4 percent were screened.

Among those without health insurance, 56.3 percent had up-to-date mammography screening.

The CDC recommends that women ages 40 to 49 talk to their doctor about when and how often they should be screened for breast cancer. Women ages 50 to 74 should have a screening mammogram every two years, the agency says.

Financial assistance is available for women without insurance. The National Breast and Cervical Cancer Early Detection Program has federal funding for low-income, uninsured and underserved women to have access to timely breast and cervical cancer screening and diagnostic services.