Many studies have shown that a shorter course of radiation treatment for breast cancer patients is just as a effective as a longer course.  However, breast cancer patients are still receiving radiation therapy for almost double the amount of time needed, a new study reports.

Of the millions of women involved in the data analysis, two-thirds of women who have had lumpectomies–breast-conserving surgeries–undergo five to seven weeks of radiation therapy. Four studies from the American Society of Radiation Oncology have concluded that three to four weeks of more intense radiation therapy called hypofractionated whole breast radiation is just as effective. Not only is the shorter course of radiation cheaper, studies have found it is preferred by most patients.

Health insurers and doctors are saying that very few of the 60 to 75 percent of women who get lumpectomies are receiving the shorter treatment since changing ingrained medical procedures takes time, according to the NY Times. It is particularly difficult because the conventional treatment has been in place for decades and the new one does not offer any additional medical benefits. The shorter course saves money for health insurers and time for the patients.

The study published in The Journal of the American Medical Association analyzed data from 14 commercial insurance plans from 15,643 women who received radiation after their lumpectomies. Radiation is used after a woman has a lumpectomy in order to reduce the chances of another cancer forming in the breast, and it betters the chances of survival.

The study found that 34.5 percent of early-stage breast cancer patients older than 50 in 2013 received the short course of radiation. Researchers, led by assistant professor of radiation oncology, health policy and medical ethics at the University of Pennsylvania Dr. Justin Bekelman, said that this percentage is higher than the 11 percent using the shorter radiation plan in 2008. However, the study found that the use of the three-week treatment accelerated in Canada. In 2008, more than 70 percent of patients with early-stage breast cancer were already receiving the treatment.

In a university news release, Bekelman said that the shorter course of radiation is still not used frequently in the U.S. despite its high quality and that it is “patient-centric cancer care” at a low cost. Bekelman added that it is “clinically equivalent” to the conventional radiation course in working toward curing breast cancer.  He said it also allows patients to return home or to work sooner, it is more convenient for patients and it has similar side effects.

Dr. Gary M. Freedman, another author of the study and breast radiation oncologist at the University of Pennsylvania, explained that it was drilled in his head not to use shorter, more intense radiation during his residency. He was told it could cause a “bad cosmetic result.”  But with the better methodology and equipment, he says that the cosmetic results are equally as good and the tide has “started turning.”

Chief of surgical oncology at Lenox Hill Hospital in New York City, Dr. Stephanie Bernik, said that the reasons behind the continued use of the six to seven weeks of treatment need to be examined to “further elucidate why there has been a slow transition.” She added that women need to be asking their radiation oncologists if they qualify for the shorter course of treatment during this transition.