The Board shall be composed of five members appointed by the Secretary without regard to the provisions of title 5 governing appointments in the competitive services. Two of such members shall be representative of providers of services. All of the members of the Board shall be persons knowledgeable in the field of payment of providers of services, and at least one of them shall be a certified public accountant. Members of the Board shall be entitled to receive compensation at rates fixed by the Secretary, but not exceeding the rate specified (at the time the service involved is rendered by such members) for grade GS–18 in section
5332 of title
5. The term of office shall be three years, except that the Secretary shall appoint the initial members of the Board for shorter terms to the extent necessary to permit staggered terms of office.