In the past few years, the number of marriage immigrants and foreign workers living in South Korea has increased rapidly. According to statistics from the Ministry of Interior in 2015, of the 1,711,013 foreign nationals living in South Korea, 144,912 (8.05%) were married to immigrants and 93,249 (5.4%) were married to naturalized persons; 83~89% of these individuals were women [1]. This increasing number of international marriages and migrant workers has led to an increasing number of adolescents from multicultural backgrounds. Indeed, according to youth statistics from 2016, the number of students from multicultural families reached 82,536 in 2015, or 1.4% of the total number of students, which was an 24.0% increase from 2012 [2]. Since South Korea is rapidly transforming into a multicultural society, it would be important task to ensure that people with diverse backgrounds can successfully integrate into and live safely within Korean society.

Adolescence is a psychologically unstable developmental stage, and when adolescents' interaction with their surrounding environment is problematic, they are at high risk of developing extreme thoughts and taking extreme action, such as death with despair [3]. suicide ideation is a logical precedent of suicide attempts and behaviors. Indeed, the stronger the suicide ideation, the greater the likelihood of attempting suicide [4]. Adolescents are known to be more likely to express their thoughts of suicide [5]. According to statistics released by the Statistics Korea, suicide is the main cause of deaths among adolescents in South Korea from 2007. In 2014, it was reported that the rate of suicide was 7.4 per 100,000 people [2]. The Korea Youth Policy Institute conducted a “survey on the mental health status of 2012 Korean children and adolescents” in 8,745 elementary, middle and high school students. In this sample, 23.4 % of respondents indicated that they had thought about suicide [6].

It has been reported that, in the adolescent period, when individuals are typically beginning to form their identity, children of multicultural families are at an increased risk to experience identity crisis and confusion that is more severe than that experienced by their Korean families [7]. Not only are these individuals possibly more vulnerable to anxiety about social acceptance and the fear of rejection, but they also tend to not receive support at home [8]. Therefore, it is not surprising that one study found a rate of depression in this population of 18.2%[9]. Further, in a study comparing suicide behaviors among adolescents of multicultural families and adolescents in the general population, Kim and Kim [10] reported that the risk of suicide was higher when the father, or if both parents were foreigners.

Researchers have shown that being from a multicultural family can influence adolescents' psychology, including their likelihood of attempting suicide. In particular, children of multicultural families in South Korea tend to experience emotional difficulties because of social prejudice and discrimination [11], low socioeconomic status, and psychological and social maladjustment [12]. These factors in turn generate stress and increase the likelihood of negative coping behaviors [34]. Such coping behaviors include health risk behaviors such as drinking and smoking, the likelihood of which is already high in adolescence [13, 14]. Another report has shown that drugs, depression, school violence, drinking, and family conflicts are relate to suicidal thoughts [15].

Conversely, as the level of mother's education increased, and as income level of the family increases, the level of child's achievement motivation, self-esteem, and learning activity also increases. There have also been studies reporting that the level of psychological behavioral development of multicultural adolescents is higher than typical adolescents [16]. In other words, multicultural families should not be considered as a homogeneous group and should not be necessarily perceived as vulnerable. This is because the academic and psychological development levels of their children often vary according to environmental factors, such as parental education and income level. Therefore, rather than providing support for multicultural adolescents only by considering the specificity of multiculturalism, the development of integrated programs, which include Korean adolescents in crisis and keeps the commonalities of all adolescents in mind, can be more effective at incorporating multicultural adolescents into Korean society and increasing the acceptance of multicultural adolescents by Korean adolescents.

While the precise factors have differed among researchers, in general, the factors influencing suicidal behavior can be grouped into social, home environment, personality, mental-health-related, and stressful-life-event-related factors. In particular, mental-health-related factors such as depression and anxiety have been attracting attention as major contributors to suicidal thoughts and attempts [17, 18]. Park [19] conducted a study on suicide attempts of Korea adolescents based on the 2006 youth online survey data. Park stated that the factors influencing suicide attempts were varied, and included personal characteristics and health behavior. This was especially true for suicidal thoughts, factors related to mental health (depression, stress, and happiness), health risk behaviors (perceived health status, drinking, smoking, drug use, sexual activity, absence of breakfast, presence of disease), and personal characteristics (co-residence type, academic achievement). Based on the data of the youth online survey in 2012, Park et al., who conducted studies on suicide ideation in multicultural adolescents, found that health-related variables (alcohol, drugs), mental health (happiness, depression), economic conditions, and school violence experience affected suicide ideation [15]. These two studies occurred at different time points, only one group was examined for factors influencing suicide ideation and attempts, and some of the variables explored were also different. Therefore, it is difficult to directly compare what factors influenced suicide attempts and ideation among Korean and multicultural adolescents in Korea. Thus, it cannot be argued that the factors influencing suicidal ideation are the same or different between the two groups.

The present study was conducted to investigate and compare the risk factors influencing suicide ideation among adolescents from multicultural families and Korean families by same dataset, and to provide basic data for the development of one comprehensive programs for the prevention of suicide of adolescents itself not differentiate Korea or multicultural. The specific purposes of this study are as follows: (1) to analyze the rates of suicide ideation among adolescents from multicultural and Korean families; (2) to analyze what general characteristics of these two groups of adolescents relate to suicide ideation; (3) and to determine and compare the relationship between general characteristic factor, health risk behavior, psychological variables and suicide ideation in two groups.

This study was a secondary analysis of national survey data. The purpose of the current study was to compare the rate of suicide ideation and the factors of multicultural and Korean adolescents. A composite sample analysis method was used to analyze survey data designed to reflect the gender, age, and demographic structure of the population [20]. As a result of the survey, the percentage of Korean and multicultural adolescents were 99% to 1%, respectively. According to 2015 statistics, the percentage of multicultural household adolescents (middle and high school students) in Korea was 1.4%, As the current data reflects the percentage, it is likely to accurately depict the actual situation of multicultural adolescents in Korea [2].

To our knowledge, this is the first nationally representative study which compare the prevalence of suicide ideation and influencing factors among adolescents from multicultural families and Korean families using same dataset in South Korea. As noted above, the suicide rate among Korean adolescents is a serious public health issue. In this study, the suicide ideation rate of adolescents was 11.3% among adolescents from Korean families and 15.8% among adolescents from multicultural families. This result is lower than that of Park [19], who reported that 23% of Korean adolescents attempted suicide, in a study using 2006 youth online data. Further, the current rate is lower than 2011 data where suicide attempts were reported by 22.4% of multicultural adolescents [12], and 2012 data where suicidal thoughts of multicultural adolescents were reported at 21.2%[15]. Although the suicide rate of adolescents is decreasing, deaths from suicide are still ranked as the number one cause of adolescent death. It is possible that the rate of adolescents thinking about suicide is artificially low. This is because these individuals may avoid thinking about the pain of reality. However, this does not accurately represent the high rate of actual attempts among those who feel suicidal. Therefore, Korean society still must take preventive measures against suicidal ideation in youth.

In this study, the general characteristics that related to the suicide ideation of adolescents were different in two groups. There were notable differences in characteristics related to suicide ideation between Korean and multicultural families. Among Korean adolescents, gender, area of residence, perceived economic status, co-residence type, and academic performance. but in multicultural adolescents, gender, area of residence, academic achievement were not significant.

In a previous study [22], gender demonstrated a significant relationship with suicide ideation in Korean adolescents. These results are inconsistent with a study that shows that the relationship between gender and suicide ideation was not significant in multicultural adolescents [15]. However, in the logistic analysis of the current study, gender affected suicide ideation in both groups, with female being 1.43 times more likely in the Korean group and 13.16 times more likely in multicultural group to display suicide ideation, when compared to males.

Also, area of residence and academic performance was not related to suicide ideation in adolescents from multicultural families, but it was in adolescents from Korean families. In the logistic analysis, neither the residence area, nor academic achievement of the two groups had any effect on suicide ideation. This result is different from previous studies, which reported academic achievement as a factor influencing suicide ideation among Korean adolescents [6], and worry about academic achievement and admission to upper school as factors that caused suicidal thoughts among multicultural adolescents [2].

Perceived economic status and co-residence type were also common characteristics related to suicide ideation in both groups of adolescents. However, in the logistic analysis, it was found that Korean adolescents were influenced by their co-residence type while perceived economic status influenced multicultural adolescents. This is consistent with the results of a study in which suicide attempts were more frequent among families of lower socioeconomic status [10], and among single parent families and adolescents raised by their grandparents [6]. In other words, living with family members in a stable living environment, whether Korean or multicultural, increases psychological stability, resulting in less suicide ideation.

Overall, the home environment variables appear more influential of the suicide ideation of adolescents than do individual factors such as academic performance. This accords with a meta-analysis of the protective factors associated with suicide ideation in adolescents [23], wherein the effect size of the family environment variables was statistically significant.

In the analysis of the prevalence of suicide ideation according to health risk behaviors and psychological factors, the factors associated with suicide ideation among adolescents from Korean families were perceived health status, alcohol drinking, smoking, perceived happiness, perceived stress, depression, and experience of violence. Those among adolescents from multicultural families, perceived health status, alcohol drinking, perceived happiness, perceived stress, depression, and experience of violence were related to suicide ideation.

Notably, the odds of suicide ideation were higher in only Korean adolescents when they perceived themselves as unhealthy. This agrees with one study showing that greater perceived health was associated with lower suicide ideation [7]. However, it is not consistent another study [15] reporting that suicide ideation and health status were not related. This discrepancy is perhaps because health status is how one feels about one's physical condition at the time of investigation; as such, it is perhaps unrelated to continuous or repetitive suicide ideation.

Alcohol drinking and smoking were related to suicide ideation in adolescents from Korean families, among multicultural adolescents, only alcohol drinking was related to suicide ideation. However, in logistic analysis, smoking alone was a significant factor for suicide ideation among adolescents in multicultural families. These results are somewhat consistent with a study wherein suicide ideation was higher among alcohol drinking and smokers [7], as well as a study wherein suicide ideation was only related to alcohol drinking [15]. Health risk behaviors such as alcohol drinking and smoking can serve as a mechanism for the release of mental pressure. In other words, health risk behaviors such as drinking and smoking may lead to suicidal thoughts, while those who actually commit suicide may reduce their thoughts by drinking and smoking. This is because smoking rates and drinking rates of adolescents in multicultural families are lower than those of Korean families [24], and smoking rates and drinking rates of multicultural families are higher than those of general household adolescents [25]. Therefore, this relationship seems to require further research to analyze what are the causes and long-term results through longitudinal study.

Perception of happiness was associated with suicide ideation in both groups, but logistic analysis showed that suicidal ideation among Korean adolescents were more associated with the perception of unhappiness. The results regarding happiness is consistent with a previous study showing the same [7].

Stress was associated with suicide ideation in both groups. The more stress one perceived, the more suicide ideation occurred. The magnitude of the relationship of suicide ideation with stress appears to vary from researcher to researcher, with one study [15] reporting that stress was not significantly related, and another [26] noting that it was. Jeon et al.[26] reported that stress related to family, peer, and teacher relationships were main factors influencing adolescents' suicide ideation. The relationship between suicide ideation and stress in adolescents seems to reflect a special situation of adolescents in Korea, and their experience of stress due to overly competitive academic environment.

Depression was associated with suicide ideation in both groups. Depression is considered to be the most direct cause of suicide, and in a study of college students in Korea, depression has proven to significantly predict suicidal ideation [27]. However, around 14.3% of children of married immigrants have been reported to experience depression or helplessness [28], thus indicating that adolescents from multicultural families are more likely to feel depressed and experience suicide ideation than are Korean adolescents. Thus, the former population would require particular management.

The experience of violence was related to suicide ideation in both Korean and multicultural adolescents. This is consistent with the results of previous studies [29]. Note that violence in this study is not only physical violence but also verbal and emotional violence. If adolescents in multicultural families experience difficulties in adapting to school because of differences in appearance and language development or linguistic and emotional conflicts with peers or seniors, it may lower their confidence and increase their depression and stress. This, in turn, would predict a likelihood of suicide ideation.

These results suggest that Korean adolescents and multicultural adolescents display similar causes of suicide ideation such as stress, depression, and violence victimization experiences. Korean adolescents were more likely to display suicide ideation when they did not live with their families or considered themselves unhappy. However, multicultural adolescents displayed more suicidal when they felt that their economic status was bad. Living with one's family and economic status are the family environment factors surrounding adolescents. This suggests that it is necessary to provide a supplementary program that can substitute for a negative family environment for both groups, as negative family environment may effect adolescents emotionally and result in suicide.

This study has a clear strength in its inclusion of data from 72,060 adolescents from a nationally representative sample in South Korea, which improves the external validity of the study results. However This study has the following limitations in the application and interpretation of our results.

First, it cannot capture adolescents' period of residence in South Korea, their frequency of use of the Korean language, or their country of birth. These are likely to affect participants' level of adaptation, and thus their likelihood of suicide. Second, depressive mood and perceived stress was only measured with a single item each, rather than with standardized multi-item measures. This may limit the validity of the measurements of these variables. Third, this study is a cross-sectional study, so it is difficult to ensure causality in epidemiological studies, and has limitation in generalize. it will be interpretate only for adolescents in South Korea.

Even within the context of these limitations, the results of the present study indicate that approximately 11.3% and 15.8% of adolescents from Korean and multicultural families, respectively, engaged in suicide ideation, which in turn, were associated with family environment and psychological problems. Therefore, rather than only providing support for local communities of multicultural adolescents by considering the specificity of multiculturalism, the development of integrated programs that include all adolescents in crisis could be more effective in helping multicultural adolescents to assimilate to Korean society.

However, the cross-sectional nature of this study limits our understanding of the influencing factors; thus, future prospective studies are required in order to identify the casual relationships among suicide ideation and various risk factors.