1.Predictive factors of adolescents’ happiness: a random forest analysis of the 2023 Korea Youth Risk Behavior Survey
Eun Joo KIM ; Seong Kwang KIM ; Seung Hye JUNG ; Yo Seop RYU
Child Health Nursing Research 2025;31(2):85-95
Purpose:
This study aimed to identify predictive factors affecting adolescents’ subjective happiness using data from the 2023 Korea Youth Risk Behavior Survey. A random forest model was applied to determine the strongest predictive factors, and its predictive performance was compared with traditional regression models.
Methods:
Responses from a total of 44,320 students from grades 7 to 12 were analyzed. Data pre-processing involved handling missing values and selecting variables to construct an optimal dataset. The random forest model was employed for prediction, and SHAP (Shapley Additive Explanations) analysis was used to assess variable importance.
Results:
The random forest model demonstrated a stable predictive performance, with an R2 of .37. Mental and physical health factors were found to significantly affect subjective happiness. Adolescents’ subjective happiness was most strongly influenced by perceived stress, perceived health, experiences of loneliness, generalized anxiety disorder, suicidal ideation, economic status, fatigue recovery from sleep, and academic performance.
Conclusion
This study highlights the utility of machine learning in identifying factors influencing adolescents’ subjective happiness, addressing limitations of traditional regression approaches. These findings underscore the need for multidimensional interventions to improve mental and physical health, reduce stress and loneliness, and provide integrated support from schools and communities to enhance adolescents’ subjective happiness.
2.Predictive factors of adolescents’ happiness: a random forest analysis of the 2023 Korea Youth Risk Behavior Survey
Eun Joo KIM ; Seong Kwang KIM ; Seung Hye JUNG ; Yo Seop RYU
Child Health Nursing Research 2025;31(2):85-95
Purpose:
This study aimed to identify predictive factors affecting adolescents’ subjective happiness using data from the 2023 Korea Youth Risk Behavior Survey. A random forest model was applied to determine the strongest predictive factors, and its predictive performance was compared with traditional regression models.
Methods:
Responses from a total of 44,320 students from grades 7 to 12 were analyzed. Data pre-processing involved handling missing values and selecting variables to construct an optimal dataset. The random forest model was employed for prediction, and SHAP (Shapley Additive Explanations) analysis was used to assess variable importance.
Results:
The random forest model demonstrated a stable predictive performance, with an R2 of .37. Mental and physical health factors were found to significantly affect subjective happiness. Adolescents’ subjective happiness was most strongly influenced by perceived stress, perceived health, experiences of loneliness, generalized anxiety disorder, suicidal ideation, economic status, fatigue recovery from sleep, and academic performance.
Conclusion
This study highlights the utility of machine learning in identifying factors influencing adolescents’ subjective happiness, addressing limitations of traditional regression approaches. These findings underscore the need for multidimensional interventions to improve mental and physical health, reduce stress and loneliness, and provide integrated support from schools and communities to enhance adolescents’ subjective happiness.
3.Predictive factors of adolescents’ happiness: a random forest analysis of the 2023 Korea Youth Risk Behavior Survey
Eun Joo KIM ; Seong Kwang KIM ; Seung Hye JUNG ; Yo Seop RYU
Child Health Nursing Research 2025;31(2):85-95
Purpose:
This study aimed to identify predictive factors affecting adolescents’ subjective happiness using data from the 2023 Korea Youth Risk Behavior Survey. A random forest model was applied to determine the strongest predictive factors, and its predictive performance was compared with traditional regression models.
Methods:
Responses from a total of 44,320 students from grades 7 to 12 were analyzed. Data pre-processing involved handling missing values and selecting variables to construct an optimal dataset. The random forest model was employed for prediction, and SHAP (Shapley Additive Explanations) analysis was used to assess variable importance.
Results:
The random forest model demonstrated a stable predictive performance, with an R2 of .37. Mental and physical health factors were found to significantly affect subjective happiness. Adolescents’ subjective happiness was most strongly influenced by perceived stress, perceived health, experiences of loneliness, generalized anxiety disorder, suicidal ideation, economic status, fatigue recovery from sleep, and academic performance.
Conclusion
This study highlights the utility of machine learning in identifying factors influencing adolescents’ subjective happiness, addressing limitations of traditional regression approaches. These findings underscore the need for multidimensional interventions to improve mental and physical health, reduce stress and loneliness, and provide integrated support from schools and communities to enhance adolescents’ subjective happiness.
4.Impact of trauma center care on mortality in Gangwon Province in Korea
Hyun Seong KIM ; Yoon-Seop KIM ; Hye Sim KIM ; Chan Young KANG ; Oh Hyun KIM ; Kang Hyun LEE ; Gyo Jin AHN
Journal of the Korean Society of Emergency Medicine 2024;35(5):335-344
Objective:
Although controversial, there is a consensus that regional trauma centers have survival benefits over nonregional trauma centers. In a predominantly rural province with a single regional trauma center, this study compared the inhospital mortality of all trauma patients and severely injured patients between regional and non-regional trauma centers.
Methods:
Using the data from the National Emergency Department Information System in Korea, this study examined all trauma patients who visited emergency departments in Gangwon Province between January 2015 and December 2017. The International Classification of Disease-Based Injury Severity Score (ICISS) was used to categorize the severity of the patients. Propensity score matching was used to balance the severity between the two groups.
Results:
Of 23,510 trauma patients, 2,857 and 20,653 were treated in regional and non-regional trauma centers, respectively. After propensity score matching, all patients in the non-regional trauma center group had a 6.27-fold higher risk of mortality than those in the regional trauma center group; severely injured patients, which were defined as those with ICISS <0.9, in the non-regional trauma center group had a 4.90-fold higher risk of mortality than those in the regional trauma center group. The ICISS cutoff values for mortality were 0.9015 and 0.8737 for the non-regional and regional trauma center groups, respectively.
Conclusion
The conventional paradigms of trauma systems can be used in predominantly rural Korean provinces, because trauma care has better survival benefits in regional trauma centers than in non-regional trauma centers. In addition, severely injured patients should be transported to regional trauma centers from the trauma scene.
8.Epidemiological and Clinical Characteristics of Women Living with HIV in Korea
Sang Min AHN ; Yong Seop LEE ; Min HAN ; Jung Ah LEE ; Jae Eun SEONG ; Yae Jee BAEK ; JongHoon HYUN ; Jung Ho KIM ; Jin Young AHN ; Dong Hyun OH ; Su Jin JEONG ; Ji Hyeon BAEK ; Nam Su KU ; Hee Kyoung CHOI ; Yoonseon PARK ; BumSik CHIN ; Young Keun KIM ; Joon Sup YEOM ; Young Hwa CHOI ; Jun Yong CHOI
Infection and Chemotherapy 2024;56(3):369-377
Background:
While Korea maintains a low prevalence of human immunodeficiency virus (HIV), the number of newly diagnosed cases has been steadily rising, reaching approximately 1,000 annually in recent years. The 2022 annual report from the Korea Disease Control and Prevention Agency revealed that women living with HIV (WLWH) constitute 6.4% of the total confirmed people living with the HIV population, totaling 1,219 individuals. Despite this, only a few studies have focused on WLWH in Korea. This study aims to analyze the epidemiological and clinical characteristics of WLWH in Korea.
Materials and Methods:
We retrospectively collected data by reviewing the medical records of all WLWH who visited 10 urban referral hospitals across Korea between January 2005 and May 2023.
Results:
A total of 443 WLWH were enrolled in this study. The predominant risk exposure was heterosexual contact, with 235 (53%) participants either married or cohabiting with a male partner at their initial clinic visit. Among the participants, 334 (77.7%) were Korean, 27 (6.1%) were Southeast Asian, and 19 (4.3%) were African. Antiretroviral therapy was initiated by 404 WLWH (91.2%). We observed 118 pregnancies in WLWH following their HIV diagnosis, resulting in 78 live births (66.1%), 18 induced abortions (15.2%), 10 pre-viable fetal losses (8.5%), and four stillbirths (3.4%). Over a cumulative follow-up duration of 3,202.1 years, the incidence rates of breast and cervical cancers were both 2.18 per 1,000 person-years. Additionally, the incidence rates of pelvic inflammatory disease, cervical intraepithelial neoplasm (above grade II), and osteoporosis were 4.67, 11.21, and 13.39 per 1,000 patient-years, respectively.
Conclusion
This is the first multicenter study to investigate the clinical and epidemiological characteristics of WLWH in Korea. The incidence and prevalence of diseases in women, including breast cancer, cervical cancer, and chronic comorbidities, are high in WLWH in Korea; therefore, further research and efforts are needed to manage these diseases.
10.Epidemiological and Clinical Characteristics of Women Living with HIV in Korea
Sang Min AHN ; Yong Seop LEE ; Min HAN ; Jung Ah LEE ; Jae Eun SEONG ; Yae Jee BAEK ; JongHoon HYUN ; Jung Ho KIM ; Jin Young AHN ; Dong Hyun OH ; Su Jin JEONG ; Ji Hyeon BAEK ; Nam Su KU ; Hee Kyoung CHOI ; Yoonseon PARK ; BumSik CHIN ; Young Keun KIM ; Joon Sup YEOM ; Young Hwa CHOI ; Jun Yong CHOI
Infection and Chemotherapy 2024;56(3):369-377
Background:
While Korea maintains a low prevalence of human immunodeficiency virus (HIV), the number of newly diagnosed cases has been steadily rising, reaching approximately 1,000 annually in recent years. The 2022 annual report from the Korea Disease Control and Prevention Agency revealed that women living with HIV (WLWH) constitute 6.4% of the total confirmed people living with the HIV population, totaling 1,219 individuals. Despite this, only a few studies have focused on WLWH in Korea. This study aims to analyze the epidemiological and clinical characteristics of WLWH in Korea.
Materials and Methods:
We retrospectively collected data by reviewing the medical records of all WLWH who visited 10 urban referral hospitals across Korea between January 2005 and May 2023.
Results:
A total of 443 WLWH were enrolled in this study. The predominant risk exposure was heterosexual contact, with 235 (53%) participants either married or cohabiting with a male partner at their initial clinic visit. Among the participants, 334 (77.7%) were Korean, 27 (6.1%) were Southeast Asian, and 19 (4.3%) were African. Antiretroviral therapy was initiated by 404 WLWH (91.2%). We observed 118 pregnancies in WLWH following their HIV diagnosis, resulting in 78 live births (66.1%), 18 induced abortions (15.2%), 10 pre-viable fetal losses (8.5%), and four stillbirths (3.4%). Over a cumulative follow-up duration of 3,202.1 years, the incidence rates of breast and cervical cancers were both 2.18 per 1,000 person-years. Additionally, the incidence rates of pelvic inflammatory disease, cervical intraepithelial neoplasm (above grade II), and osteoporosis were 4.67, 11.21, and 13.39 per 1,000 patient-years, respectively.
Conclusion
This is the first multicenter study to investigate the clinical and epidemiological characteristics of WLWH in Korea. The incidence and prevalence of diseases in women, including breast cancer, cervical cancer, and chronic comorbidities, are high in WLWH in Korea; therefore, further research and efforts are needed to manage these diseases.

Result Analysis
Print
Save
E-mail