What is the test for an employee to be found guilty of negligence in a medical malpractice case?

Walker v. Lykes Bros., 193 F.2d 772, 773 (2d Cir.1952). "The theory [behind the rule] apparently is that a momentary inattention to one's own safety ... should not be treated as so serious a fault as the breach of a duty assumed by the employee for the protection of others, although incidentally it is for his own benefit too." Id. at 774.