Ohio Rev. Code Ann. § 2305.251
(B)
(1) A hospital shall be presumed to not be negligent in the credentialing of an individual who has, or has applied for, staff membership or professional privileges at the hospital pursuant to section 3701.351 of the Revised Code, and a health insuring corporation or sickness and accident insurer shall be presumed to not be negligent in the credentialing of an individual who is, or has applied to be, a participating provider with the health insuring corporation or sickness and accident insurer, if the hospital, health insuring corporation, or sickness and accident insurer proves by a preponderance of the evidence that, at the time of the alleged negligent credentialing of the individual, the hospital, health insuring corporation, or sickness and accident insurer was accredited by one of the following:
(2) The presumption that a hospital, health insuring corporation, or sickness and accident insurer is not negligent as provided in division (B)(1) of this section may be rebutted only by proof, by a preponderance of the evidence, of any of the following: