Proceedings before the board wherein a licensee's right to practice medicine in this state is terminated, suspended, or limited or wherein a public reprimand is administered shall require prior notice to the licensee and an opportunity for hearing; and such proceedings shall be considered contested cases within the meaning of Chapter 13 of Title 50, the "Georgia Administrative Procedure Act." Neither refusal of a license nor a private reprimand shall be considered a contested case within the meaning of Chapter 13 of Title 50, and notice and hearing within the meaning of such chapter shall not be required; but the applicant physician shall be allowed to appear before the board if he so requests. The power to subpoena as set forth in Chapter 13 of Title 50 shall include the power to subpoena any book, writing, paper, or document. If any licensee fails to appear at any hearing after reasonable notice, the board may proceed to hear the evidence against such licensee and take action as if such licensee had been present.