Two advocacy groups asked the government Thursday to halt a nation-wide research project that is testing 30-hour work shifts for novice doctors, a practice that was banned in 2011.

Public Citizen and the American Medical Student Association asked the Department of Health and Human Services to stop the experiment now taking place at 63 medical programs across the country. The two groups contend that the research is unethical because neither the physicians nor their patients are given the opportunity to consent to the arrangement.

The research poses "serious health risks," including the possibility of car accidents and depression for first-year internal medicine physicians who must work the lengthy shifts, Public Citizen said in a letter to the government's Office for Human Research Protections. The research also creates additional risk for their patients, the organization wrote.

The two groups also asked the Accreditation Council for Graduate Medical Education to rescind a waiver it issued in order to allow the experiment. The council banned 30-hour shifts for first year doctors at accredited medical programs in 2011, limiting them to no more than 16 consecutive hours at work.

The study, and a previous, similar one involving young surgeons, has reopened one of the oldest debates in the training of newly-graduated doctors. Those who favor the long shifts say that novice physicians learn best by following patients for as long as possible and that handing patients off to other physicians unfamiliar with their cases is actually more dangerous than treatment by inexperienced, sleep-deprived doctors.

The two studies seek to determine whether patient care is affected by the long shifts, and whether the doctors themselves are affected. Results from the study among surgeons will be available in February, but results from the study of internal medicine physicians are not expected until 2019.

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