In a medical malpractice action, the defendant hospital appeals from so much of an order of the Supreme Court, Queens County, dated September 28, 1977, as (1) granted, to a stated extent, plaintiffs’ motion to vacate appellant’s demand for a bill of particulars and (2) denied appellant’s cross motion for a protective order with respect to plaintiffs’ demand for a bill of particulars relating to affirmative defenses pleaded in its answer. Order modified by deleting therefrom the provision that appellant’s motion for a protective order is denied in its entirety and by substituting therefor provisions that the cross motion is granted to the extent of striking paragraph "second” of plaintiffs’ demand for a bill of particulars and that the cross motion is otherwise denied. As so modified, order affirmed insofar as appealed from, without *977costs or disbursements. The respective demands for bills of particulars in this case sought irrelevant matter and directed the production of evidentiary materials, as opposed to a "General statement of the acts or omissions constituting the negligence claimed” (see CPLR 3043, subd [a], par [3]). A bill of particulars is not intended to be of aid to a party in obtaining evidentiary material. Its purpose is to amplify the pleadings, limit proof and prevent surprise at trial (Cirelli v Victory Mem. Hosp., 45 AD2d 856; cf. Nelson v New York Univ. Med. Center, 51 AD2d 352). We note that plaintiffs have not cross-appealed. Latham, J. P., Rabin, Gulotta and O’Con-nor, JJ., concur.