June 2011

Objectives: This study aimed to quantify the extent to which socioeconomic-related inequality in self-reported oral health status among Thais is present after the country implemented the Universal Coverage policy and to decompose the determinants and their associations with inequality in self-reported oral health status in particular with the worse condition. Design and Method: The study employed a concentration index to measure socioeconomic-related inequality in self-reported oral health status, and the decomposition method to identify the determinants and their associations with inequality in oral health-related measures. Data from 32,748 Thai adults aged 15-75 years from the nationally representative Health &Welfare Survey and Socio-Economic Survey 2006 were used in analyses. Results: Reports of worse oral health status of the lower socioeconomic-status group were more common than their higher socioeconomic-status counterparts. The concentration index (equaling -0.208) corroborates the finding of pro-poor inequality in self-reported worse oral health. Decomposition analysis demonstrated certain demographic-, socioeconomic-, and geographic characteristics are particularly associated with poor-rich differences in self-reported oral health status among Thai adults. Conclusions: This study demonstrated socioeconomic-related inequality in oral health is discernable along the entire spectrum of socioeconomic status. Inequality in perceived oral health status among Thais is present even while the country has virtually achieved universality of health coverage. The study also indicates population subgroups, particularly the poor, should receive consideration for improving oral health status as revealed by underlying determinants. Key words: Decomposition, determinants, inequality, self-reported oral health, Thailand, universal coverage