Hospital use behaviors and associated costs in a health insurance organization, Japan.

Physicians are known to play an important role in the rise of health care costs. But patients--the other side of the chain of health care systems--have been given little attention. The present study utilized the outpatient claims (in the belief that the outpatient hospital visits are mainly decided by the patients) from a health insurance organization in Japan (the Fukuoka Prefecture public service mutual aid association for government employees who serve in small cities, towns, and villages) to analyze the employee behaviors in the use of hospital care and the costs associated with these behaviors. Number of diseases diagnosed for an employee, number of claims an employee submitted for one disease, number of hospitals an employee visited, number of claims an employee had from one hospital, and the total number of claims an employee submitted were used to describe the hospital use behaviors. Results showed that some employees exhibited unusual behaviors, characterized by having an extremely large number of diseases diagnosed, visiting a large number of different hospitals, having a large number of claims, etc. Higher medical expenditures were associated with such behaviors. The findings of this study suggest that the patients' role in the rise of health care costs cannot be ignored, and cost-containment strategies targeting modification of patient behaviors in the use of hospital care may prove to be very useful.