Vassos v. Roussalis
In Vassos v. Roussalis, 625 P.2d 768, 772-73 (Wyo. 1981), the Court wrote:
".A malpractice action is usually a form of a negligence action. It is in this instance. Accordingly, the elements necessary to sustain a negligence action must be here proven, i.e., a duty on the part of the defendant, failure to perform the duty proximately causing damage to plaintiff. The determination of the standard of care or duty is a matter of law and not the province of the jury.
In this case, the existence of the physician-patient relationship established the duty. The standard is fixed as that which is required of a reasonable person in the light of all the circumstances. Some circumstances have acquired particular legal significance which make it possible for the court to fix a more specific standard . . . . A malpractice contention is also one of those circumstances. The more specific standard for malpractice actions is that a physician or surgeon must exercise the skill, diligence and knowledge, and must apply the means and methods, which would reasonably be exercised and applied under similar circumstances by members of his profession in good standing and in the same line of practice.
. . .
When the circumstances in which the fictitious reasonable person acts are within the common knowledge of the jury, the jury does not need assistance in comprehending the standard fixed by the court. But when such circumstances are not of such common knowledge, the jury must depend upon testimony of experts to explain the standard and thus prevent a conclusion based on conjecture and speculation. In other words, an additional question of fact must be answered when the circumstances are such that the reasonable person standard is not within the common knowledge of the jury."