Heeran J. Cho

Background: The global rise in smartphone addiction among children is linked to increasing mental, physical, familial, and financial problems. This study aimed to longitudinally explore the impact of sibling smartphone addiction on child smartphone addiction. While the influences of parental smartphone addiction and peer groups on smartphone addiction have been studied, more research is needed to examine the longitudinal effects of sibling smartphone addiction, a significant family member during childhood, on child smartphone addiction. Methods: This study conducted a longitudinal analysis using four years of panel data (2019– 2022) from the Korean Children and Youth Panel Survey (KCYPS). The final analysis included a total of 1,978 participants, comprising fourth-grade elementary school children (n=989) and their siblings (n=989). The changes in smartphone addiction over the four years were analyzed using latent growth analysis. Results: First, while the rate of change in child smartphone addiction was higher, both sibling and child smartphone addiction increased over time. Lower initial smartphone addiction levels were linked to a greater increase in smartphone usage over time. These results indicate the need for interventions targeting groups with lower initial levels of smartphone addiction. Second, higher initial levels of sibling smartphone addiction were associated with greater child smartphone addiction, and the change rate of sibling smartphone addiction influenced that of child smartphone addiction. As sibling smartphone addiction sharply increased over time, child smartphone addiction similarly escalated dramatically. On the other hand, it was found that as sibling smartphone addiction increases gradually, child smartphone addiction also increases gradually. Conclusion: This study identified the longitudinal impact of sibling smartphone addiction on the onset and progression of child smartphone addiction. The findings suggest that when preventing and intervening in the risk of child smartphone addiction, it is effective to consider the issue of sibling smartphone addiction in a long-term context.

Purpose: This study analyzed the longitudinal relationship between smartphone addiction and sleep duration to investigate the factors contributing to sleep deprivation in Korean children. Methods: To overcome the limitations of previous studies, panel quantile regression analysis was used to evaluate the relationship between smartphone addiction and sleep duration. Key variables were smartphone addiction, sleep duration, gender, and age. Results: According to the study results, the level of smartphone addiction among children significantly increased from 2018 to 2022, while sleep duration continuously decreased. A particularly strong negative relationship between smartphone addiction and sleep duration was found. Conclusion: These results suggest that smartphone addiction is strongly associated with sleep deprivation in children, emphasizing the need for policies and intervention measures to create a healthy sleep environment for children.

Objective Concerns about the low fertility and population decline are increasing worldwide, and Korea has the lowest fertility rate in the world. This study aims to comprehensively examine the policies implemented by local governments and investigate the longitudinal impact of fertility subsidy policy on the fertility rate in Korea. Method The study utilized data on the total fertility rate of local governments from 2014 to 2018. Data analysis was conducted via SPSS 25.0 and M-plus 8.0 software. Model fit was assessed using TLI (Tucker-Lewis Index), CFI (Comparative Fit Index), and RMSEA (Root Mean Square Error of Approximation). Results The results showed a significant relationship between the rate of change in the fertility subsidy and the rate of change in the fertility rate (B=.006, p<.01). Specifically, as the fertility subsidy increased rapidly over time, the fertility rate gradually decreased. Conversely, a gradual increase in the fertility subsidy led to a sharp decline in the fertility rate. Conclusion To effectively increase the fertility rate in South Korea, it is crucial to implement comprehensive policies that take into account social, economic, and demographic factors, as well as the findings of this study regarding fertility support. Highlights

Background: Korean government has established various policies to counter the low fertility rate since the mid-2000s, but it still has the lowest fertility rate among OECD member countries. This study investigated the relationship between changes in the Korean fertility rate and policies to encourage fertility. Methods: This study utilized data of the total fertility rate of 250 local governments between 2014 and 2018, and a casebook of local government birth promotion policies. The dependent variable was fertility rate, and the independent variable was fertility promotion policy. Using SPSS 25.0 and M-plus 8.0 programs, descriptive statistical analysis and latent growth modeling were conducted. An unconditional quadratic function change model was selected as a final model of this study. Results: The average of the initial fertility rate and the linear rate of change in the Korean fertility rate, and the rate of change of the quadratic function were all statistically significant, meaning that the fertility rate of decline increases over time. Also, the linear rate of change and the quadratic function change rate were significant, showing significant differences in the initial level and rate of change of the fertility rate between local governments. Among fertility policies, only the in-kind policy had a significant effect on the initial value of the fertility rate, meaning that the higher the number of in-kind policies, the higher the fertility rate. Conclusion: This study is crucial as it examined the changes in the fertility rate of Korean local governments as well as the policy factors affecting the fertility rate at a quantitative level.

While smoking is a crucial health risk, it adversely affects oral health, particularly becoming riskier for older adults who have smoked for a long time. This study identifies the patterns of smoking behavior changes in older adults aged 65 years and older and examines how the smoking behavior changes affect their oral health. Longitudinal data were derived from Korean Longitudinal Study of Aging (KLoSA) between 2006 and 2018, targeting the older adults 65 years and older in South Korea. The independent variable was the amount of smoking, and the dependent variable was oral health. For data analysis, SPSS 25.0 and M-plus 8.0 programs were utilized. As a result, the patterns of changes in smoking behavior of the older adults finally derived were ‘non-smoking,’ ‘decreasing,’ ‘high-level maintenance,’ and ‘decreasing after increasing.’ Furthermore, the relationship between the smoking behavior change pattern of the older adults and oral health was revealed. Specifically, as for the smoking behavior change pattern of the older adults, it was confirmed that the oral health was better in the ‘non-smoking’ pattern compared to the ‘high-level maintenance’ pattern. On the other hand, it was confirmed that the ‘decreasing’ pattern and the ‘decreasing after rising’ pattern did not significantly affect oral health. The findings imply that even if older adults smoked a lot in the past, if they quit smoking at some point, it can positively affect their oral health. Furthermore, it is suggested to allow public officials, medical professionals, and welfare experts to actively intervene for older adults to stop smoking for their oral health.

This study aimed to investigate the moderation of social support in the association between loneliness and depression in different age groups of older adults. The sample consisted of 1532 community-dwelling adults aged 65 years or older, based on the data from the National Social Life, Health, and Aging Project (NSHAP), Wave 3 (2015–2016). Eleven items of the Center for Epidemiologic Studies Depression Scale (CES-D) were used to measure depressive symptoms. Similarly, a four-item scale was used to measure social support (each from spouse and family), and a three-item scale for loneliness. The results were as follows. Loneliness was associated with depression in both the young-old and the old-old groups. Spousal support and family support were associated with reduced depression in the young-old group, whereas only spousal support was associated with relieving depression in the old-old group. Social support had a significant moderating effect on the relationship between loneliness and depression in the old-old group, whereas it had no significant effect in the young-old group. From these results, it can be concluded that spousal support plays a significant role in seniors’ mental health. The role of caregivers for a person’s well-being grows later in life, so practitioners could help couples communicate with this consideration. In addition, regular contacts with family members and spousal support are recommended to prevent older old adults’ depression.

Background: Longitudinal studies of drinking behavior have reported inconsistent changes in drinking behavior as people age. Thus, this study aims to characterize the changes in drinking behavior among Korean adults and to reveal differences in their demographics, depression, and suicidal thoughts. Methods: This study used the Korea Welfare Panel Study data over nine years (2009 to 2017), analyzing a total of 7506 participants. Growth mixture modeling was applied to classify patterns of change in drinking in these participants. The χ² test and analysis of variance were used to analyze the differences in demographics, depression, and suicidal thoughts according to patterns of change in drinking. Results: Changes in drinking among Korean adults were categorized into four types: “high-risk retention”, “medium-risk to high-risk”, “high-risk to low-risk”, and “low-risk retention”. Gender, age, education, marital status, living arrangement, living area, and depression differed among these groups. Conclusion: We identified four types of changes in adult drinking behavior in South Korea, which varied in their demographics and depression levels. These results suggest that tailoring interventions to the type of behavioral changes might be more useful than batch interventions.

Background: Smartphone addiction among children and adolescents has a negative effect, as excessive use of smartphones can cause physical symptoms, such as fatigue, indigestion, and sleep problems, as well as psychopathological problems, such as depression, anxiety, and impulsiveness. Materials and Methods: This study was carried out using the Korean Children and Youth Panel Survey 2019 conducted by the National Youth Policy Institute. The total number of participants was 4656 youths (2290 in grade 5 and 2366 in grade 8), and the dependent and independent variables were smartphone addiction in children and parents, respectively. Multiple regression analysis was conducted by Stata 15.0 SE. Results: First, the level of parents’ smartphone addiction affected that of children and adolescents. Second, the children’s and adolescents’ age affected the level of smartphone addiction, while their gender did not affect it. Third, the relationship between the levels of parents’ and children’s smartphone addiction was not moderated by the genders and ages of the children and adolescents. Conclusions: It was confirmed that as parents’ smartphone addiction increased, that of children increased, and smartphone addiction was found to increase in the second grade of middle school (12 years old) rather than grade 5 of elementary school (10 years old). Parents’ and children’s smartphone addiction was not moderated by children’s and adolescents’ gender and age.

Background: Smartphones are an important part of children’s and adolescents’ lives, and they often spend a lot of time using them. This study aims to precisely discover the effects of smartphone addiction on sleep duration as moderated by age and gender. Materials and methods: The data utilized in this study are from the ‘Korean Children and Youth Panel Survey 2018′ by the National Youth Policy Institute; a total of 4940 youths (2399 in grade 4 and 2541 in grade 7) from the survey were analyzed by Stata 15.0 S. The dependent variable is sleep duration, and the independent variables are the sub-factors of smartphone addiction: disturbance of adaptive functions, virtual life orientation, withdrawal, and tolerance. An independent t-test was conducted to confirm the differences in the main variables according to gender and age. Multiple regression analysis was conducted to verify the moderating effects of gender and age in the relationship between children’s smartphone addiction and sleep duration. Results: First, the average sleep duration among grade 4 students was 9.17 h and grade 7 students was 7.96 h. Second, sleep duration was significantly higher for males than females, while there was no difference in smartphone addiction by gender. Third, smartphone addiction, particularly the sub-factor of tolerance significantly affected sleep duration. Fourth, age significantly affected sleep duration and gender had a moderating effect on sleep duration. Conclusions: Interventions to develop a healthy smartphone usage culture on family and societal levels would be beneficial for increasing awareness of smartphone addiction and its adverse effects on children and adolescents. Furthermore, targeted intervention would be more effective at modifying addictive behavior and sleep duration than trying to administer blanket interventions to youths as a whole.

Background: Korea had the highest suicide rate among OECD countries for the 10 years leading up to 2016; however, the suicide rate in Korea has declined since 2010, after policy-driven interventions were implemented. Methods: Suicide rates from all of the 229 cities, counties, and districts in Korea were reliably estimated from the period 2010 to 2017, and data were examined by Stata 14.0 and M-plus to identify regional suicide rate change patterns by latent growth modeling. The dependent variable is the suicide rate, and independent variables as characteristics of the various districts are the region (cities, counties, and autonomous districts), proportion of elderly residents, financial independence rate, establishment of mental health and welfare centers, and number of social welfare facilities. Results: Three suicide rate change patterns were identified: ‘average’, ‘precipitous drop’, and ‘high level’. Two of the three patterns exhibit features that are markedly different to the national data as a whole, and the three patterns appear across the 229 cities, counties, and districts of Korea. Some of the determinant factors have been postulated here. While a high proportion of elderly residents in a given area is a significant indicator that the suicide rate will increase, having a large elderly population in combination with an increased number of social welfare facilities centers appeared to show a discrete pattern of suicide rate reduction when compared with average national data. Conclusions: Policy-driven interventions should be planned and implemented by central and local governments in conjunction, by considering regional characteristics to decrease local suicide rates more effectively.