OPINION OF THE COURT

Memorandum.

The order of the Appellate Division should be affirmed, with costs.

The Appellate Division correctly concluded that defendant laboratory made a prima facie showing of its entitlement to summary judgment. As stated by that court, defendant submitted proof to the effect that the blood test was properly performed, that defendant did not interpret the test results, and that the negative test result it obtained could have been correct even though a different laboratory obtained a positive result on a sample of decedent’s blood drawn two months later. In light of that showing, the affidavit of plaintiff’s medical expert was insufficient to raise a material issue of fact *900(see, Alvarez v Prospect Hosp., 68 NY2d 320, 324-325; Winegrad v New York Univ. Med. Center, 64 NY2d 851, 853). Indeed, the expert’s conclusory assertion that defendant’s negative result was erroneous simply because of the later positive result raised no issue of fact at all; even if plaintiffs proof were fully credited by a fact finder, defendant has offered proof to the effect that there could be different results without any negligence, and plaintiff has offered nothing further to indicate defendant’s negligence in this case.

Chief Judge Wachtler and Judges Simons, Kaye, Alexander, Titone, Hancock, Jr., and Bellacosa concur.

Order affirmed, with costs, in a memorandum.