Heterogeneity in dentists’ activity in Taiwan: an application of quantile regression

Abstract

The purpose of this paper is to provide new evidence on heterogeneity in dentists’ activity. The heterogeneity is of particular importance because dentists’ responses are likely to differ widely from high to low activity dentists. Quantile regressions provide an alternative and useful method to investigate the differential responses of dentists to various observable explanatory variables. The results reject the null hypothesis of homoskedasticity of individual dentists’ responses. It is shown that time trends for dentists at higher quantiles have greater fluctuations than those at lower quantiles. The clinic–hospital gap in activity at higher quantiles is greater than at low quantiles. Clinic dentists at higher quantiles have much higher numbers of visits and numbers of treatments than those at lower quantiles, but they provide less intensity of care. Dentists in deprived areas have higher activity than those in non-deprived areas, only when they are located at higher quantiles. The results may help policy makers to focus on responsive targets in order to improve the effectiveness of their recent policy of global budgeting.