Michigan Compiled Laws, Chapter 600. Revised Judicature Act of 1961 § 600.5838

Sec. 5838. (1) Except as otherwise provided in section 5838a or 5838b,  1 a claim based on the malpractice of a person who is, or holds himself or herself out to be, a member of a state licensed profession accrues at the time that person discontinues serving the plaintiff in a professional or pseudoprofessional capacity as to the matters out of which the claim for malpractice arose, regardless of the time the plaintiff discovers or otherwise has knowledge of the claim.

(2) Except as otherwise provided in section 5838a or 5838b, an action involving a claim based on malpractice may be commenced at any time within the applicable period prescribed in sections 5805 or 5851 to 5856,  2 or within 6 months after the plaintiff discovers or should have discovered the existence of the claim, whichever is later. The plaintiff has the burden of proving that the plaintiff neither discovered nor should have discovered the existence of the claim at least 6 months before the expiration of the period otherwise applicable to the claim. A malpractice action that is not commenced within the time prescribed by this subsection is barred.