• 응용통계연구
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• 제29권7호
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• pp.1231-1246
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• 2016

경쟁위험에 대한 연구 중 주로 쓰이는 방법은 Cause-specific 위험 모형과 subdistribution을 이용한 비례 위험 모형 방법이다. 그 이후에도 많은 모형이 제시되었지만, 추정 방법 면에서 설명력이 부족하거나 알고리즘으로 구현하기 어려운 단점을 가지고 있어서 잘 활용되고 있지 않다. 이 논문에서는 Cause-specific 위험 모형, subdistribution을 이용한 비례 위험 모형과 비교적 최근에 제시된 이항 회귀 모형(direct binomial model), 절대 위험 회귀 모형(absolute risk regression model), Eriksson 등 (2015)의 비례 오즈 모형(proportional odds model)을 소개하고 추정 방법을 간단히 설명하고자 한다. 각 모형에 대하여 SAS와 R을 이용한 활용 방법을 제시하고, 두 가지 경쟁위험이 존재하는 데이터를 R을 이용하여 분석하였다.

• 대한가정학회지
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• 제36권11호
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• pp.91-101
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• 1998

The purpose of this study was to identify which of the variables were associated with ineffective parental child-rearing practices and to examine the effects of cumulative risk factors on ineffective child-rearing practices. The subjects for this study consisted of 120 mothers and 120 fathers of two to six year old children attending a university child development laboratories. Self-report questionnaire were used to collect data on the following variables: 1) family backgrojnd characteristics; 2) child temperament; 3) quality of life; 4) social support; 5) intergenerational trasmission of parenting; and 6) parental disciplinary practices. Descriptive analysis, t-test, and chi-square analyses were used for data description and analysis. The major findings were as follows: 1) Mothers who perceived the child as being less emotional, more soothable, and who had higher levels of marital satisfaction and job satisfaction engaged in more effective child-rearing practices. 2) Fathers who perceived the child as being less emotional, and who have boys provided more effective child-rearing practices. 3) For both mothers and fathers, parents with higher levels of quality life, social support, and family income exhibited more effective child-rearing practices. 4) Parents exposed to several risk factors were much more likely to exhibit ineffective child-rearing practices than parents exposed to no risk factors. The results of this study indicate that the characteristics of the child, parent, and contextual factors all contribute to the parental child-rearing pracitices.

• 한국학교보건학회지
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• 제14권2호
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• pp.269-277
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• 2001

This study examined the health conditions of schoolteachers in terms of the prevalence rate and risk factors for liver disease. A cohort design was conducted for 21,319 teachers who were born from 1953 to 1957. The cohort was constructed for teachers who had no disease history such as liver disease, hypertension, cerebral vascular disease, heart disease, diabetes mellitus and cancer, and had 'normal' results from liver disease examinations in 1998. They were followed up from 1998 to 2000. SAS 6.12 was used for the data analysis. The results were as follows; (1) Prevalence rates of liver disease per 1,000 people in 1998 were 43.0. (2) The 2-year cumulative incidence of liver disease was 433/16,103(26.9/1000 persons). (3) Factors such as sex, age, school type(private or public), drinking, smoking, exercise, BMI, weight gain, fasting-blood sugar levels and total cholesterol levels were statistically significant. The significant risk factors of liver disease be identified from the multiple logistic regression analysis were age, sex(male), drinking, smoking, BMI, weight gain, fasting-blood sugar levels, and total cholesterol levels.

• Child Studies in Asia-Pacific Contexts
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• 제7권1호
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• pp.15-26
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• 2017

The aim of this study was to retrospectively estimate the prevalence of childhood emotional abuse (CEA), childhood physical abuse (CPA), and childhood contact sexual abuse (CCSA) in relation to adult poor mental health, addictive behavior, and other health-risk behaviors among university students in five ASEAN countries (Indonesia, Malaysia, Myanmar, Thailand, and Vietnam). In a cross-sectional survey, 3,240 undergraduate university students were randomly selected (M age = 20.5 years, SD = 1.6 years) to respond to a questionnaire including the Abuse section of the World Health Organization (WHO) Version 1 "Adverse Childhood Experiences International Questionnaire" (ACE-IQ) and other measures. The students reported 17.9% CEA, 28.2% CPA, and 22.4% CCSA, with the highest prevalence of CEA in Myanmar (30.9%) and CPA and CCSA in Vietnam (55.8% and 41.6%, respectively). In logistic regression models, adjusting for sociodemographic and social variables, the separate and cumulative effects of three types of child abuse (emotional, physical, and sexual) were found to increase the risks for poor adult mental health, addictive, and other health-risk behaviors.

• 한국환경과학회지
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• 제25권9호
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• pp.1311-1322
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• 2016

Since the scale and disaster characteristics of volcanic eruptions are determined by their geological features, it is important not only to grasp the current states of the volcanoes in neighboring countries around the Korean Peninsula, but also to analyze the tectonic settings, tectonic regions, geological features, volcanic types, and past eruptional histories of these volcanoes. We created a database of 285 volcanoes around the Korean Peninsula, and then identified a high-risk groups of 29 volcanoes that are highly likely to affect the region, based on conditions such as volcanic activity, the type of rocks at risk of eruption, the distance from Seoul, and high VEI (volcanic explosivity index). In addition, we identified the 10 volcanoes that should be given the highest priority. We selected them through an analysis of data available in literature, such as volcanic ash dispersion results from previous Japanese eruptions, the definition of a large-scale volcano used by Japan's Cabinet Office, and examination of cumulative magma layer volumes from Japan's quaternary volcanoes.

• 대한치과보철학회지
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• 제45권1호
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• pp.48-59
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• 2007

Statement of problems: There are few studies which reported the survival rates of the specific dental implant systems in the Korean population with the follow-up periods longer than 5 years. Purpose: This retrospective clinical study was aimed to evaluate cumulative survival rate (CSR) of $Br{\aa}nemark$ implants followed for 10 years and to determine risk factors for implant failure. Material and methods: A total of 271 $Br{\aa}nemark$ implants in 83 patients were investigated with several identified risk factors. Life table analysis was undertaken to examine the CSR. Cox regression method was conducted to assess the association between potential risk factors and overall CSR. Results: Thirty implants failed. The 10-year implant CSR was 82.5%. Cox regression analysis demonstrated a significant predictive association between overall CSR and implant length (P<.05). Conclusion: An acceptable long-term result of $Br{\aa}nemark$ implant was achieved and implant length showed a significant association with the CSR.

• Nuclear Engineering and Technology
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• 제40권7호
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• pp.539-550
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• 2008

Lung cancer is the most prevalent global cancer, ${\sim}90%$ of which is caused by cigarette smoking. The LNT hypothesis has been inappropriately applied to estimate lung cancer risk due to ionizing radiation. A threshold of ${\sim}1\;Gy$ for lung cancer has been observed in never smokers. Lung cancer risk among nuclear workers, radiologists and diagnostically exposed patients was typically reduced by ${\sim}40%$ following exposure to <100 mSv low LET radiation. The consistency and magnitude of reduced lung cancer in nuclear workers and occurrence of reduced lung cancer in exposed non-worker populations could not be explained by the HWE. Ecologic studies of indoor radon showed highly significant reductions in lung cancer risk. A similar reduction in lung cancer was seen in a recent well designed case-control study of indoor radon, indicating that exposure to radon at the EPA action level is associated with a decrease of ${\sim}60%$ in lung cancer. A cumulative whole-body dose of ${\sim}1\;Gy$ gamma rays is associated with a marked decrease in smoking-induced lung cancer in plutonium workers. Low dose, low LET radiation appears to increase apoptosis mediated removal of $\alpha$-particle and cigarette smoke transformed pulmonary cells before they can develop into lung cancer.

• Investigative and Clinical Urology
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• 제59권6호
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• pp.399-409
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• 2018

Purpose: To analyze data from an observational, prospective, cumulative registry study in 805 hypogonadal men stratified by mild or moderate-to-severe lower urinary tract symptoms (LUTS) according to International Prostate Symptom Score. Materials and Methods: A total of 412 men underwent testosterone therapy (TTh) with injectable testosterone undecanoate, 393 men served as untreated controls. Measures of urinary function, anthropometric and metabolic parameters were performed at least twice per year. Results: Data from 615 men with mild LUTS (253 treated, 362 untreated) and 190 with moderate-to-severe LUTS (159 treated, 31 untreated) were available. During a follow-up period of 8 years a significant improvement of LUTS was noted for all TTh-patients whereas the control-groups showed deterioration or fluctuation around initial values. Despite advancing age, TTh fully prevented worsening of symptoms. In parallel, a considerable improvement of anthropometric parameters, lipids and glycemic control, blood pressure, C-reactive protein, and quality of life was found. Moderate-to-severe LUTS was associated with worse cardiometabolic risk profile at baseline as well as worse cardiovascular outcomes during follow-up in comparison to mild LUTS. Effect size of TTh was more pronounced in men with moderate-to-severe than with mild LUTS. Conclusions: Correcting hypogonadism by TTh is highly effective and safe for improving LUTS in hypogonadal men. TTh may also improve cardiometabolic risk and major adverse cardiovascular events.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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• pp.647-653
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• 2016

Background: Breast cancer is the most common type of cancer affecting Malaysian women. Recent statistics revealed that the cumulative probability of breast cancer and related deaths in Malaysia is higher than in most of the countries of Southeast Asia. Single nucleotide polymorphisms (SNPs) in CYP2E1 (rs6413432 and rs3813867), STK15 (rs2273535 and rs1047972) and XRCC1 (rs1799782 and rs25487) have been associated with breast cancer risk in a meta-analysis but any link in Southeast Asia, including Malaysia, remained to be determined. Hence, we investigated the relationship between these SNPs and breast cancer risk among Malaysian women in the present case-control study. Materials and Methods: Genomic DNA was isolated from peripheral blood of 71 breast cancer patients and 260 healthy controls and subjected to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Results: Our study showed that the c1/c2 genotype or subjects with at least one c2 allele in CYP2E1 rs3813867 SNP had significantly increased almost 1.8-fold higher breast cancer risk in Malaysian women overall. In addition, the variant Phe allele in STK15 rs2273535 SNP appeared to protect against breast cancer in Malaysian Chinese. No significance association was found between XRCC1 SNPs and breast cancer risk in the population. Conclusions: This study provides additional knowledge on CYP2E1, STK15 and XRCC1 SNP impact of risk of breast cancer, particularly in the Malaysian population. From our findings, we also recommend Malaysian women to perform breast cancer screening before 50 years of age.

• Fisheries and Aquatic Sciences
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• 제7권3호
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• pp.141-147
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• 2004

Sixteen polycyclic aromatic hydrocarbons (PAHs) were analyzed in seventy marine organisms (40 species) from the Korean coast. PAHs were present in all the organisms. The level of total PAHs in the organisms varied from 0.45 to 224 ng/g dry weight and the carcinogenic PAHs varied from 0.05 to 49.8 ng/g dry weight. The PAHs residues according to the marine organisms showed a highest content in bivalve species, and followed by crustaceans, cephalopods, fish and gastropods. Human dietary intake of total PAHs through marine organism in Korea was estimated to be 4.12 ng/kg body weight/day and 0.67 ng/kg body weight/day for carcinogenic PAHs. The relative contributions of individual species to the total dietary intake of PAHs were in the order of bivalves $(53.4{\%})$, fish $(21.9{\%})$, crustaceans $(15.3{\%})$, cephalopods $(8.8{\%})$ and gastropods $(0.6{\%})$. Daily dietary intake of $PAH_{TEQ}$ expressed as a TEQ value was estimated to be 0.13 pg TEQ/kg body weight/day, which did not exceed a tolerable daily intake (TDI) proposed by the KFDA and the WHO as well as the UK toxicity committee. Lifetime cancer risk due to ingestion of marine species by the Korean adult was evaluated using the equation estimating exposure of food ingestion. Although approximately $23{\%}$ of cumulative frequency of the sampled marine species exceeded the cancer risk guideline, lifetime cancer risk associated with marine organism consumption was negligible. Results indicate that dietary intake of PAHs through the consumption of the Korean marine organisms seems to be safe for human ingestion with negligible cancer risk.