Miss. Code Ann. § 41-83-21

Notwithstanding language to the contrary elsewhere contained herein, if a licensed physician certifies in writing to an insurer within seventy-two (72) hours of an admission that the insured person admitted was in need of immediate hospital care, such shall constitute a prima facie case of the medical necessity of the admission. To overcome this, the entity requesting the utilization review and/or the private review agent must show by clear and convincing evidence that the admitted person was not in need of immediate hospital care.