International Journal of Public Health

, Volume 61, Issue 5, pp 613–620 | Cite as

Decomposing socioeconomic inequalities in the use of preventive eye screening services among individuals with diabetes in Korea

  • Jongnam HwangEmail author
Original Article



The aim of this study was to assess the socioeconomic inequalities in the use of preventive eye screening services among individuals with diabetes in Korea.


Using nationally representative survey data, the concentration index (CI) and decomposition of the CI were used to capture and quantify income-related inequalities.


The results show income-related inequality in the use of eye screening services among individuals with diabetes, suggesting that services were concentrated among individuals with higher incomes. After adjusting for need factors, such as sex, age and self-rated health, the inequality still persisted as observed horizontal inequity in the services, indicating that unequal care was provided for equal need. The decomposition approach revealed that the largest contributions to the observed inequality were higher education and higher income levels. Having private insurance and residing in non-Seoul metro areas also contributed to the observed pro-rich inequality.


These findings suggest that income- and education-related barriers to the use of preventive eye screening services for individuals with diabetes should be targeted for removal at the national level to achieve the goal of equal care for equal need in diabetes management.


Concentration index Decomposition Diabetes Preventive eye care services Inequality Socioeconomic status 



The author is grateful to Dr. Patricia O’Campo and ACHIEVE (Action for Health Equity Interventions) Post-Doctoral Fellows at St. Michael’s Hospital, Canada, for their critical comments on an earlier version of this paper.


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Copyright information

© Swiss School of Public Health (SSPH+) 2016

Authors and Affiliations

  1. 1.Department of Health PromotionDaegu UniversityGyeongsan-SiRepublic of Korea

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