external appeals (Insurance Law § 4911), as well as to review the activities of the external appeal agents, investigate complaints by insureds concerning requests for and processing external appeals and to conduct random audits to determine the external appeal agents' compliance with title II (Insurance Law § 4916). The procedure for external appeals of adverse determinations is set forth in section 4914 of the Insurance Law. Considering the statutory scheme, I find that external appeal agents function in an administrative capacity on behalf of the state. Furthermore, IPRO is a not-for-profit corporation, which comes within the definition of a "body" against whom an article 78 proceeding will lie (Schiffer v Tarrytown Boat Club, 219 AD2d 704 [1995], appeal dismissed 87 NY2d 916 [1996], rearg denied 87 NY2d 1056 [1996], cert denied 519 US 864 [1996], reh denied 519 US 1023 [1996]; Matter of Sines v Opportunities For Broome, 156 AD2d 878 [1989]). Under the circumstances, an article 78 proceeding is the proper vehicle for reviewing the determination of IPRO to uphold the health plan's denial of coverage. Insofar as IPRO alleges that petitioner will be unable to meet the "arbitrary and capricious" standard, this determination should be made after service of the answer.