Do you think you would be better at your job if you weren't allowed to work for more than 80 hours per week? What if you were forced to clock out after working for 28 hours in a row? If you're a new doctor in your first years of training after medical school, the answer seems to be no. Two studies published Tuesday in the Journal of the American Medical Assn. examined the effects of new work rules that limit the number of hours interns and residents can spend caring for hospital patients. In both studies, researchers found little to no evidence that patients fared better or worse after the new rules went into effect in 2011.