Several recent reports have suggested that mammography may not be as effective as medical experts claim. According to new evidence from four Swedish studies, though, the procedure significantly reduces breast cancer deaths. More than 245,000 women were followed for more than sixteen years in the studies. A woman's risk of dying from breast cancer was nearly twenty-one percent lower for those who received mammograms than for those who did not. Researchers involved in the study insist early detection is crucial to breast cancer survival and that the mammogram remains the most effective tool for detecting malignant growths.