Explaining socioeconomic inequality differences in catastrophic health expenditure between urban and rural areas of iran after health transformation plan implementation

Objective: Ensuring fair financial contribution is one of the main goals of the Health Transformation Plan (HTP) of Iran. This study aims to estimate socioeconomic inequality differences in catastrophic health expenditure (CHE) between urban and rural areas of Iran after the implementation of the HTP during 2017. Materials and Methods: Data from a representative survey of households’ income and xpenditure from the Iran Statistical Center (ISC) were used for the analysis. We applied the World Health Organization (WHO) cut-off of 40% payment for CHE, and Wagstaff’s normalized concentration index (C) to measure and decompose the inequality. Also, Blinder–Oaxaca decomposition analysis was used to decompose contributors of inequality differences between rural and urban areas. Results: The overall incidence of CHE among Iranian households during the year 2017 was 3.32% with a standard deviation (SD) of 17.91%, and the mean (SD) levels of CHE in rural and urban areas of Iran were 4.37% (20.45%) and 2.97% (16.99%), respectively. The aggregate socioeconomic status (SES)-related inequality in CHE was significantly (p<0.001) different from zero (C=−0.238) and there was a significant (p<0.05) difference between rural (C=-0.150) and urban (C=0.218) areas. SES was the highest contributor to inequality in both rural (130.09) and urban (144.17) areas. The Blinder–Oaxaca decomposition revealed that SES (175.01%) followed by outpatient services (120.29%) were the main contributors to differences in inequality in rural and urban areas. Sex (−101.42%) and health insurance coverage were among negative contributors to this inequality difference. Conclusion: Our findings revealed a significant pro-rich inequality in CHE. Also, some variables, such as sex and region, made different contributions in rural and urban areas. However, SES, itself, made the highest contribution in both areas and explained the greatest share of difference in inequality between the two areas. This issue calls for revision of the HTP to further address the risk of CHE and socioeconomic disparity among Iranian house-holds, especially those with lowSES.