• Safety and Health at Work
• /
• v.2 no.1
• /
• pp.70-82
• /
• 2011

Objectives: Ischemic heart disease (IHD) is a major cause of death in Korea and known to result from several occupational factors. This study attempted to estimate the current magnitude of IHD mortality due to occupational factors in Korea. Methods: After selecting occupational risk factors by literature investigation, we calculated attributable fractions (AFs) from relative risks and exposure data for each factor. Relative risks were estimated using meta-analysis based on published research. Exposure data were collected from the 2006 Survey of Korean Working Conditions. Finally, we estimated 2006 occupation-related IHD mortality. Results: For the factors considered, we estimated the following relative risks: noise 1.06, environmental tobacco smoke 1.19 (men) and 1.22 (women), shift work 1.12, and low job control 1.15 (men) and 1.08 (women). Combined AFs of those factors in the IHD were estimated at 9.29% (0.3-18.51%) in men and 5.78% (-7.05-19.15%) in women. Based on these fractions, Korea's 2006 death toll from occupational IHD between the age of 15 and 69 was calculated at 353 in men (total 3,804) and 72 in women (total 1,246). Conclusion: We estimated occupational IHD mortality of Korea with updated data and more relevant evidence. Despite the efforts to obtain reliable estimates, there were many assumptions and limitations that must be overcome. Future research based on more precise design and reliable evidence is required for more accurate estimates.

• Health Policy and Management
• /
• v.34 no.1
• /
• pp.17-25
• /
• 2024

Background: This study aimed to assess the appropriate allocation of emergency medical beds across 17 provinces and presume the economic benefits associated with such allocation. Methods: To estimate the optimal allocation of emergency medical beds by province, data from the Statistics Korea's "cause of death statistics (2014-2021)," regional statistics on "area, population, gender, age," and "population projections" were utilized. The "number of emergency beds by city and district" provided by the Health Insurance Review and Assessment Service was also used. In estimating the economic benefits of preventing avoidable emergency deaths due to the expansion of emergency medical facilities, guidelines from the Korea Development Institute and the Korea Transport Institute were referenced to calculate the wage loss costs associated with emergency deaths and estimate the economic benefits. Results: The optimal ratio of emergency medical beds allocation by region was highest in Gyeonggi, Seoul, Gyeongnam, Gyeongbuk, and Busan, while Daejeon, Jeju, and Sejong showed lower ratios. Additionally, the prevention of avoidable deaths and economic benefits resulting from the increase in emergency medical facilities were highest in Gyeonggi, Seoul, Gyeongbuk, Gyeongnam, and Busan. However, when standardized by population, the prevention of avoidable deaths and economic benefits were analyzed to be highest in Gyeongbuk, Chungnam, Jeonnam, Gyeongnam, and Busan. Conclusion: The results of this study can serve as foundational data for future policy measures aimed at addressing the imbalance in the supply of emergency medical facilities across regions. Considering regional characteristics in the distribution of emergency medical facilities is expected to ultimately increase the efficiency of national finances and yield economic benefits.

• The Korean Journal of Applied Statistics
• /
• v.37 no.2
• /
• pp.225-237
• /
• 2024

In the analysis of competing risks data, some of covariates may not be fully observed for some subjects. In such cases, excluding subjects with missing covariate values from the analysis may result in biased estimates and loss of efficiency. In this paper, we studied multiple imputation and the augmented inverse probability weighting method for regression parameter estimation in the cause-specific proportional hazards model with missing covariates. The performance of estimators obtained from multiple imputation and the augmented inverse probability weighting method is evaluated by simulation studies, which show that those methods perform well. Multiple imputation and the augmented inverse probability weighting method were applied to investigate significant risk factors for the risk of death from breast cancer and from other causes for breast cancer data with missing values for tumor size obtained from the Prostate, Lung, Colorectal, and Ovarian Cancer Screen Trial Study. Under the cause-specific proportional hazards model, the methods show that race, marital status, stage, grade, and tumor size are significant risk factors for breast cancer mortality, and stage has the greatest effect on increasing the risk of breast cancer death. Age at diagnosis and tumor size have significant effects on increasing the risk of other-cause death.

• Journal of Environmental Health Sciences
• /
• v.49 no.6
• /
• pp.362-371
• /
• 2023

Background: PM_2.5 pollution has been a persistent problem in South Korea, with concentrations consistently exceeding World Health Organization (WHO) guidelines. The aging of the population in the country further exacerbates the health impacts of PM_2.5 since older adults are more susceptible to the adverse effects of air pollution. Objectives: This study aims to evaluate how the health impact (premature death) due to long-term exposure to PM_2.5 in South Korea could change in the future according to the trend of change in the country's population structure. Methods: The study employs a relative risk function, which accounts for age-specific relative risks, to assess the changes in premature deaths by age and region at the average annual PM_2.5 concentration for 2022 and at PM_2.5 concentration improvement levels. Premature deaths were estimated using the Global Exposure Mortality Model (GEMM). Results: The findings indicate that the increase in premature deaths resulting from the projected population structure changes up to 2050 would significantly outweigh the health benefits (reduction in premature deaths) compared to 2012. This is primarily attributed to the rising number of premature deaths among the elderly due to population aging. Furthermore, the study suggests that the effectiveness of the current domestic PM_2.5 standard would be halved by 2050 due to the increasing impact of population aging on PM_2.5-related mortality. Conclusions: The study highlights the importance of considering trends in population structure when evaluating the health benefits of air pollution reduction measures. By comparing and evaluating the health benefits in reflection of changes in population structure to the predicted PM_2.5 concentration improvements at the provincial level, a more comprehensive assessment of regional air quality management strategies can be achieved.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.12
• /
• pp.4839-4842
• /
• 2014

Background: Although the Cox's proportional hazard model is the popular approach for survival analysis to investigate significant risk factors of cancer patient survival, it is not appropriate in the case of log-term disease free survival. Recently, cure rate models have been introduced to distinguish between clinical determinants of cure and variables associated with the time to event of interest. The aim of this study was to use a cure rate model to determine the clinical associated factors for cure rates of patients with breast cancer (BC). Materials and Methods: This prospective cohort study covered 305 patients with BC, admitted at Shahid Faiazbakhsh Hospital, Tehran, during 2006 to 2008 and followed until April 2012. Cases of patient death were confirmed by telephone contact. For data analysis, a non-mixed cure rate model with Poisson distribution and negative binomial distribution were employed. All analyses were carried out using a developed Macro in WinBugs. Deviance information criteria (DIC) were employed to find the best model. Results: The overall 1-year, 3-year and 5-year relative survival rates were 97%, 89% and 74%. Metastasis and stage of BC were the significant factors, but age was significant only in negative binomial model. The DIC also showed that the negative binomial model had a better fit. Conclusions: This study indicated that, metastasis and stage of BC were identified as the clinical criteria for cure rates. There are limited studies on BC survival which employed these cure rate models to identify the clinical factors associated with cure. These models are better than Cox, in the case of long-term survival.

• Journal of Preventive Medicine and Public Health
• /
• v.25 no.2 s.38
• /
• pp.115-126
• /
• 1992

To estimate the cancer mortality rates among Koreans, a mortality survey was carried out in the province of $Ky{\breve{o}}ngsangnam-do$. The study population are the beneficiaries of Korea Medical Insurance Corporation(KMIC), $Ky{\breve{o}}ngsangnam-do$ area, among which the 3,867 deaths occurred from January, 1989 to December, 1990, were reviewed to confirm the cancer deaths. These were based upon the death certificates and medical utilization records before dying which were available through the computerized databases on medical care utility of KMIC. The survey was conducted along three steps. At first, the death certificates were examined, as a second step medical utilization records were reviewed, and finally direct contacts to the family members of the deceased were done. As a result, 990 deaths were found due to cancer. Using them, age and sex specific cancer(all sites and several sites) mortality rates were estimated. Overall cancer mortality rate in the area was estimated 138.7 per 100,000 person-years in males, and 65.7 in females, respectively. And the orders of site-specific cancer mortality rates were the cancers of stomach, liver, lung, esophagus, and cancers of the hematopoietic system among males, In females, followed by gastric cancer, cancers of lung and liver are the 2nd and 3rd in rank, respectively and cancers of breast and uterine cervix are the 4th and the 5th in rank.