Investigating Appropriate Threshold for Measuring the Occurrence and Intensity of Households' Exposure to Catastrophic Health Expenditure in Iran

Background and Objectives: Fair financial protection against health expenditures is one of the most critical goals of health systems. This study was conducted to investigate the most appropriate threshold for measuring the exposure to catastrophic health expenditure (CHE) in Iran.   Methods: The present study was conducted using 2018 national household income and expenditure data of the Iran statistics center. The occurrence and intensity of the households' exposure to CHE at different thresholds and for economic quintiles was measured using two World Health Organization (WHO) and World Bank (WB) methodologies. The most appropriate threshold for each methodology was also determined using the Kappa statistics adaptation estimation.   Results: The occurrence of households’ exposure to CHE was 3.02% and 8.51% in urban households and 4.66% and 9.22% in rural households, respectively. According to asset quintiles, the highest occurrence was in the first quintile and the lowest in the fifth quintile. In addition, the results of adaptation estimation based on Kappa statistics showed that a threshold of 40% in the WHO methodology and 25% in the WB methodology were the most appropriate thresholds.   Conclusion: The results showed a relatively high rate of exposure to CHE. CHE occurrence was also more in poorer households, and common thresholds were the most appropriate thresholds for estimating CHE.