London ? Women who get regular mammograms could reduce their risk of dying from breast cancer by 28 percent, new research indicates.

The study is the largest yet to investigate the survival benefits of routine breast X-rays. Conducted by a team of scientists from Sweden, Britain, Taiwan and the United States, the research was based on 210,000 women aged 20 to 69 in Sweden.

Breast cancer deaths in the United States and Europe have fallen by nearly 30 percent since 1990. Experts are not sure how much of this is due to catching the disease early with mammograms.

“While mammography is largely accepted by the scientific and medical community as a benefit to women, there are still some who express doubts as to its value. This study goes a long way toward silencing the dissenting voices,” said the study’s leader, Stephen Duffy, professor of epidemiology at the Wolfson Institute of Preventive Medicine in London.

However, other experts said the research, published this week in The Lancet medical journal, did not clarify whether the drop in deaths was due to early detection from the X-rays or advances in treatment.

Researchers compared deaths from breast cancer diagnosed in the 20 years before mammogram screening was introduced with those diagnosed in the 20 years afterward.