By Jason Kane at the PBS Newshour

It’s official: CT scans reduce the risk of death for heavy smokers with lung cancer by 20 percent compared to chest X-rays.

After a nearly decade-long study, results from the National Lung Screening Trial were published Wednesday in The New England Journal of Medicine.

The findings made headlines in November 2010 when the National Cancer Institute announced that it had become clear that the group receiving three-dimensional X-ray tests known as low-dose helical CT scans had a significantly higher chance of surviving than those receiving standard chest X-ray tests.

It’s the first type of screening known to reduce the risk of death from lung cancer, despite a high rate of false positive tests from the scans.