牙醫服務誘發需求可能性之研究

Objectives: The existence of supplier-induced demand (SID) is still frequently being debated in health economics studies. Availability of appropriate research methodologies and econometric tools is a key to solve this mystery. This study aims to investigate the effect of dentist-to-population ratio on dentists' behavior in Taiwan by focusing on the level of individual dentist. Methods: Data of this study mainly came from the 1997 and 1998 National Health Insurance Research Database. The data were analyzed using a panel-instrument approach. Results: The results show that an increase in dentist-to-population ratio causes a slight increase in mean revenue per consultation per dentist, but declines in mean number of consultations and mean revenue per month per dentist. The results imply that dentists might respond to the losses due to a greater competition by increasing treatment intensity per consultation, but the magnitude was limited. Conclusion: Compared to previous reports, our results should be more accurate since we had incorporated the casemix adjustment, and included the panel data as well as instrument variable in our analysis. We suggest that government should use incentives to improve unequal distribution of dentists. Future researches can focus on the issue of demand side and investigate the possible existence of a nonlinear relationship between the level of competition and provider behavior.