North Korea’s economic difficulties after the fall and dissolution of communism in Eastern Europe and the Soviet Union and a great flood in 1995 that caused the Great Famine led to the deaths of millions of North Koreans due to starvation and hunger-related illnesses during the late 1990s . Since then, many North Korean defectors (NKDs) have escaped to South Korea. The highest concentration of military power in the world is on the border between North and South Korea, so NKDs often pass through third countries such as China, Thailand, and Laos to enter South Korea. Despite the huge barriers and great danger, the number of NKDs entering South Korea has been steady at 1000 ~ 2000 annually since 2002, and the cumulative total by September 2019 was 33,247 .
Despite the financial and medical support by Korean Government, NKDs have experienced various difficulties in settling into South Korean society and managing their health conditions . According to a survey of NKDs in 2018, 62.2% of NKDs suffered from stress in overall daily life, while only 54.4% of South Koreans suffered from stress. Furthermore, 14.6% of NKDs had suicidal thoughts compared to 5.1% of South Koreans. Moreover, a particularly notable part was that the "physical/mental illness and disability" was the second highest cause of suicidal ideation (23.3%) .
Education can be considered as one of the most critical factors that potentially affect the adjustment of NKDs to South Korean society and their health. The health effects of education attainment against risk of morbidity and mortality are well established [5–7]. High education is shown to protect against a decline in self-rated health (SRH) [8, 9], chronic disease , and mortality . As another essential component of human life, social support has been known to be associated with health and well-being. Social isolation entails a mortality risk comparable in magnitude to that of smoking, a sedentary lifestyle, obesity, and alcohol abuse .
Previous evidence suggests that education and social relationships interact with each other to affect health. Some research in this area has found that the protective effects of social support on health are stronger among individuals with high education levels [13, 14]. These studies have demonstrated that those with high levels of education benefit most from the protective qualities of social support, and the social support-health connection is almost nonexistent among those with lower levels of education. Conversely, one study found that the protective qualities of social support are stronger among individuals who are less educated . Yet, additional empirical evidence has demonstrated that social support is predictive of worse, rather than better health outcomes among individuals with a low level of education [13, 14].
Education is not only a determinant of health but also an opportunity to form social relationships. Especially for NKDs, being a part of a social community in South Korean society, such as a regular education in South Korea, provides them with good opportunities to receive social support and may have an important health-promoting impact. Previous studies [16, 17] showed that facilitating the visit of educational institutions for refugees is an essential factor for successful social inclusion.
However, literature is scarce on the exact nature of the links among education in South Korea, social support, and self-rated health status among NKDs. We hypothesized that education in South Korea, social support, and self-rated health status would be directly associated with each other. We also hypothesized that education in South Korea would be directly and indirectly associated with self-rated health status through social support. Therefore, the aims of this study was to identify the individual effects of education and social support on the self-rated health status, respectively, and then to further assess the path from education in South Korea to self-rated health status through social support among NKDs.