Notwithstanding any other provisions of this chapter the director shall establish, within 15 days of the effective date of this act a statewide, uniform schedule for reimbursing physician services to Medi-Cal patients provided on or after July 1, 1976; except that, the director may establish physician reimbursement rates higher than the statewide rates for; (a) areas which the director determines to be medically underserved: and (b) other problems of equity in payment levels which adversely affect the accessibility of physician services to Medi-Cal recipients. Nothing in this section shall be construed to prevent the director from adopting physician reimbursement rates for

primary care services and maternity care services which are relatively higher than the rates paid for other types of physician services.