For the purposes of ART review of a decision, a reference in the ART Act to the decision - maker for the decision is taken to be a reference to:
(a) the Secretary; and
(b) either of the following, if applicable:
(i) if the decision was made by the Chief Executive Centrelink or an APS employee in the Human Services Department--the Chief Executive Centrelink;
(ii) if the decision was made by the Chief Executive Medicare--the Chief Executive Medicare.