The department shall provide for a continuing study of the quality of care and services resulting from the operation of this chapter and for surveys and reports on prepaid health plans. With respect to such plans contracted for under this chapter, the department may contract with professional organizations for studies and reports of the experience of such plans as to the standards of care available to eligible persons, gross and net costs, administrative costs, benefits, utilization of benefits, the portion of actual personal expenditures of eligible persons for health care which are being met by prepaid benefits, and the methods of evaluating and improving the quality of, and controlling the costs of, health care provided under such contracts. However, this section shall not be construed to require any prepaid health plan to provide accounting data or statistical data not required by regulations adopted by the director.