Okla. Stat. tit. 19, § 792

If a county hospital is operated by a board of control, it shall be the duty of said board of control to appoint annually at the first meeting in January none other than good, competent, trained, and skilled physicians and surgeons to the medical staff of the hospital, after acceptance by the executive committee of the medical staff. Admission of patients to the hospital shall be only upon recommendation of a member of the medical staff. The medical staff shall organize and adopt rules, regulations, or bylaws for their practice in such county hospital, however, rules, regulations, or bylaws shall not become effective until approved by the board of control and when so approved they shall be signed by each member of the medical staff.