The basic function of social security including medicine and care is originally to provide a safty-net against life' risks. Added to this welfare function, there are other aspects: 1) financial and 2) industrial aspects.

1) From a viewpoint of government finance, what is needed is a shift in the concept of social security. A number of contradictions have been produced by the government's one-dimensional provision of social security services, and become pervasive with a more than anticipated aging of the population, dcline in economic growth, and accumulation of national debt.

What is needed at this juncture is to shed our more-insurance-the-better reliance on government. With regard to the social security system, a major transition needs to be made from a reliance or leaning on government to a system of self-support as means of obtaining self-actualization. Investigation is made into the form reflected intrinsic characteristics of each field: medicine and care.

2) Private enterprise should be moving aggressively toward public field by adopting effective management practices baseed on market principles, while government acts to make up market deficiencies. The various areas of the "silver business" function effectively as "quasi-regulated markets" which introduce a generating of private-sector vitality, and a competitive environment between the public and private sectors. In assuring the "equality" sought by social security, measures must concurrently be taken so as not to lose sight of "optimality".

It is desirable to expand and diversify the service menu by complementing public services with services provided by private enterprise. Silver and health markets, technical innovations in tailor-made health care, private insurance and other new fields with its large latent demand create employment and industrial activity.

Moreover, spending on social security induces an economic repercussion effect by inter-industrial activity, one that does not pale in comparison to public works spending. The way in which silver business activities manifest themselves will reshape the inter-industry structure, causing a change in the pattern of input-output multiplier effects.

It is the meaning and behavior of these aspects, outlined above, that this analysis seeks to elucidate.

We developed a data warehouse system with cost analysis, based on the categories of the diagnosis procedure combination (DPC) system, in which medical costs by DPC category were estimated using data from the Hospital Data Ware-House System and factors influencing the balance between costs and fees. The balance data of patients who were discharged from Kagoshima University Hospital from April 2003 to March 2005 were determined in terms of medical procedure, cost per day and patient admission in order to conduct a drill-down analysis.

To evaluate this system, we analyzed cash flow by DPC category of patients who were categorized as having malignant tumor and whose DPC category was re-evaluated in 2004. The percentages of medical expenses were highest in patients with acute leukemia, non-Hodgkin's lymphoma, and particularly in patients with malignant tumors of the liver and intrahepatic bile duct. Imaging tests degraded the percentages of medical expenses in Kagoshima University Hospital.

These results suggested that cost analysis by patient is important for hospital administration in the inclusive evaluation system using a case-mix index such as DPC.

There are some confusions on controversies about “mixed medical care services”. We can find the origin on differences in awareness of “market failure”, “equity”, “actual condition” and so on. Therefore, to dissolve these confusions, it is important to construct common recognitions by empirical studies. As part of efforts to develop the works, we extend Suzuki-Saito (2006) and re-examine mixed medical care services issues in the light of equity of accessibility on health-care. The results are as follows: In a case of patient with a limited life expectancy “one year” using public health-care rationings, ①permitted mixed medical care services improves income redistribution effects and does good for lower-income class. ②It was found from estimating Kakwani index that regressive degree of medical out-of-pocket was nearly constant after permitted mixed medical care services. ③We can calculate that the result is due to equivalence of increasing degrees of medical out-of-pockets between income-class. ④Then in each income-class, average ratios of medical out-of-pocket of income increase slightly. But those increases are extremely small. Therefore it seems reasonable to suppose that lower-income class does not feel burden so much. ⑤We estimate medical out-of-pocket by kernel estimation or average ratios of medical out-of-pocket within each income-class. Then, it was found that patients behave differently even if they are in same income-classes. It is concluded from the result that we can't explain patients' decision-making of medical treatment at one's own expense only due to “paying capacity”. The same things are also said of asset class. At least in a case, the results obtained were contrary to conventional suggestions. It follows from the results that it is not necessarily the case which permitted mixed medical care services makes lower income-class worse. Moreover, it is suggested that we should also consider other factors but paying capacity, which control patients' decision-making of medical treatment at one's own expense.