*2.1. Data Sources*

The source data used in this study is from the TKM usage survey of 2017, conducted by the Ministry of Health and Welfare and National Institute of Korean Medicine Development. The survey was reviewed and approved by Korea Statistics (National Certified Statistics Approval Number: 117087). As for the survey data, the researchers made a request for micro-data through the surveys on the traditional herbal medicines consumption and the TKM usage database (https://www.koms.or.kr/main.do, accessed on 18 November 2020) run by the National Institute of Korean Medicine Development (NIKOM). Approval was obtained to use and analyze the data from the NIKOM, which was commissioned by the government to conduct the above-mentioned survey and analyzed the micro-data which was provided by the said organization to conduct this study.

As for the surveys on the traditional herbal medicine consumption and the TKM usage, the survey on the usage of TKM started in 2008 (1st survey), which was followed by the survey on the consumption of traditional herbal medicine (1st survey) in 2009. In 2011, the two separate surveys were integrated into one survey on TKM usage. Since then, the survey has been conducted every 3 years. Among all the data collected over the years, we used the data on the usage of TKM obtained during the 4th survey that took place in 2017.
