• Journal of Korean Society for Quality Management
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• v.26 no.4
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• pp.111-123
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• 1998

We consider the problem of modeling count data where the observation period is determined by the life time of the system under study. We assume random effects or a frailty model to allow for a possible association between the death times and the counts. We assume that, given a random effect or a frailty, the death times follow a Weibull distribution with a hazard rate. For the counts, given a frailty, a Poisson process is assumed with the intensity depending on time. A gamma distribution is assumed for the frailty model. Maximum likelihood estimators of the model parameters are obtained. A model for the time to death and the number of failures system received is constructed and consequences of the model are examined.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.1017-1026
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• 2005

We consider the problem of modeling count data where the observation period is determined by the survival time of the individual under study. We assume random effects or frailty model to allow for a possible association between the death times and the counts. We assume that, given a random effect, the death times follow a Weibull distribution with a rate that depends on some covariates. For the counts, given the random effect, a Poisson process is assumed with the intensity depending on time and the covariates. A gamma model is assumed for the random effect. Maximum likelihood estimators of the model parameters are obtained. The model is applied to data set of patients with breast cancer who received a bone marrow transplant. A model for the time to death and the number of supportive transfusions a patient received is constructed and consequences of the model are examined.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.682-687
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• 2018

We investigated the effects of a highly saline solution (HS) containing hypochlorous acid, calcium chloride ($CaCl_2$), and phosphoric acid ($H_3PO_4$) on cell death and growth rate of laver Porphyra yezoensis and green laver Ulva intestinalis. Cell death rates of laver treated with HS and HS plus hypochlorous acid (HS + HOCl) in the harvesting stage were less than 0.5%, and there were no significant differences between the HS and HS + HOCl treatments. However, cell death of green laver treated with HS + HOCl in the harvesting stage was greater than 81.2%. These results indicate that the addition of HOCl is highly effective to eradicate noxious green laver without causing damage to laver. The addition of HOCl and $H_3PO_4$ to HS did not increase the area or weight of laver blades. A combination treatment of $CaCl_2$ and HS, however, significantly increased the area and weight of laver lades compared to controls (P<0.05).

• Health Policy and Management
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• v.21 no.2
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• pp.195-212
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• 2011

Objectives: This study investigates the relationship between nurse staffing levels and differences in patient outcomes in terms of average length of stay, in-hospital mortality rate and 30-day death rate in order to evaluate the effectiveness of a policy that differentiates fees for inpatients on the basis of nurse-to-bed ratios. Methods: We obtained information on inpatients from health insurance claims data published by the Health Insurance Review and Assessment Service(HIRA) in 2008, organizational factors(type of hospital, ownership) from the records of the hospital report system in 2008, and nurse staffing levels, which were graded on a scale of 1 to 7, from data compiled between December 15, 2007, and September 20, 2008. The data were segregated according to type of hospital and quarter and finally 3,517 records of 1,182 hospitals were analyzed using multi-level analysis. Results: The average length of stay in grade 1~6 hospitals was lower than that in grade 7 ones, but the difference was much below one day. No significant difference was found among different grades in tertiary hospitals. Further, variations in staffing levels did not result in any significant difference in the in-hospital mortality rate and 30-day death rate. Conclusions: High nurse staffing levels did not result in better patient outcomes compared with low staffing levels. We therefore recommend modifying the above nurse staffing policy so as to make it more effective in improving patient outcomes.

• Health Policy and Management
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• v.31 no.1
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• pp.100-113
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• 2021

Background: This study aims to figure out the gaps in health status by estimating amenable mortality rate by region, reflecting the characteristics of Korea, and estimating the years of life lost (YLL) per capita by disease. Methods: People who died from amenable diseases between 2008 and 2018 were extracted from the cause of death statistics provided by Statistics Korea. The age-standardized amenable mortality rates were estimated to compare the health status of 229 regions. YLL per capita was calculated to compute the burden of diseases caused by treatable deaths by region. The YLL per capita by region was calculated to identify the burden of disease caused by amenable deaths. Results: First, while the annual amenable mortality rate in Korea is on a steady decline, but there is still a considerable gap between urban and rural areas when comparing the mortality rates of 229 areas. Second, YLL per capita due to the amenable deaths is approximately 14 person-years during the analysis period (2008-2018). Conclusion: Although the health status of Koreans has continuously improved, there is still a gap in health status region by region in terms of amenable mortality rates. Amenable death accounts for a loss of life equivalent to 14 person-years per year. Since the amenable mortality rate is an indicator that can measure the performance of the health care system, efforts at each local area are required to lower it.

• Journal of Preventive Medicine and Public Health
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• v.47 no.6
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• pp.336-342
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• 2014

Objectives: Child mortality remains a critical problem even in developed countries due to low fertility. To plan effective interventions, investigation into the trends and causes of child mortality is necessary. Therefore, we analyzed these trends and causes of child deaths over the last 30 years in Korea. Methods: Causes of death data were obtained from a nationwide vital registration managed by the Korean Statistical Information Service. The mortality rate among all children aged between one and four years and the causes of deaths were reviewed. Data from 1983-2012 and 1993-2012 were analyzed separately because the proportion of unspecified causes of death during 1983-1992 varied substantially from that during 1993-2012. Results: The child (1-4 years) mortality rates substantially decreased during the past three decades. The trend analysis revealed that all the five major causes of death (infectious, neoplastic, neurologic, congenital, and external origins) have decreased significantly. However, the sex ratio of child mortality (boys to girls) slightly increased during the last 30 years. External causes of death remain the most frequent origin of child mortality, and the proportion of mortality due to child assault has significantly increased (from 1.02 in 1983 to 1.38 in 2012). Conclusions: In Korea, the major causes and rate of child mortality have changed and the sex ratio of child mortality has slightly increased since the early 1980s. Child mortality, especially due to preventable causes, requires public health intervention.

• The Korean Nurse
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• v.6 no.4 s.30
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• pp.15-30
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• 1967

• Journal of Korean Neurosurgical Society
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• v.55 no.1
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• pp.1-4
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• 2014

Objective : The case fatality rate of nonlesional intracerebral hemorrhage (n-ICH) was high and not changed. Knowing the causes is important to their prevention; however, the reasons have not been studied. The aims of this study were to determine the cause of death, to improve the clinical outcomes. Methods : We retrospectively analyzed consecutive cases of nonlesional intracerebral hemorrhage in a prospective stroke registry from January 2010 to December 2010. Results : Among 174 patients ($61.83{\pm}13.36$, 28-90 years), 29 patients (16.7%) died during hospitalization. Most common cause of death was initial neurological damage (41.4%, 12/29). Seventeen patients who survived the initial damage may then develop various potentially fatal complications. Except for death due to the initial neurological sequelae, death associated with immobilization (such as pneumonia or thromboembolic complication) was the most common in eight cases (8/17, 47.1%). However, death due to early rebleeding was not common and occurred in only 2 cases (2/17, 11.8%). Age, initial Glasgow Coma Scale, and diabetes mellitus were statistically significant factors influencing mortality (p<0.05). Conclusion : Mortality of n-ICH is still high. Initial neurological damage is the most important factor; however, non-neurological medical complications are a large part of case fatality. Most cases of death of patients who survived from the first bleeding were due to complications of immobilization. These findings have implications for clinical practice and planning of clinical trials. In addition, future conduct of a randomized study will be necessary in order to evaluate the benefits of early mobilization for prevention of immobilization related complications.

• Journal of Preventive Medicine and Public Health
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• v.7 no.2
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• pp.285-292
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• 1974

It is well known fact that many tuberculosis patients have often experienced interuption of treatment while their treatment. Because most of cases were inproved subjective symptome by adequate treatment for 3-6 months and patients misunderstood to be heal completely by their own dicision, It become the cause of emergency of drug resistance and chronic incurable diseases. The author intended to clarify the duration of treatment and its outcome by some characteristics of tuberculosis patients. The results obtained were as follows: 1. The rate of treatment for tuberculosis patients by each duration with 1-6, 7-12, 13-13, 19-24 and 25 or more months were 16, 23, 20, 14 and 25 percents respectively. The duration of treatment increased in patients with advancing age, better educated and registered at health center between 7-12 months after diagnosis for tuberculosis. 2. The rate of complete treatment, defaulters, death and migration were 43, 13, 8, and 10 percents respectively. The rate of complete treatment were high in older, better educated and registered at health center between 7-12 months after diagnosis. The rate of defaulters were high in younger, no educated and registered within 1 month after diagnosis. The rate of death was high in older and migration was high in younger.

• Clinical and Experimental Pediatrics
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• v.61 no.12
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• pp.381-386
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• 2018

Purpose: The use of proper safety restraint systems by children is vital for the reduction of traffic accident-related injury and death. This study evaluated the rates of use of safety restraint systems and front seats by Korean children. Methods: Based on data from the National Health and Nutrition Examination Survey from 2008 to 2015, I investigated the frequencies of safety restraint systems and front seat use by children under six and 12 years of age, respectively. Results: The percentage of respondents who said they always use safety restraint systems increased from 17.7% in 2008 to 45.0% in 2015. The rate of children who did not use the front seats at all was 47.3 % in 2008 compared to 33.4% in 2015. Multivariate logistic regression analysis showed a decrease in safety-restraint-system use as age increased (odds ratio, 0.63; 95% confidence interval [CI], 0.51-0.77). The use rate of front-passenger seat belts by the mother is significantly correlated with the safety-restraint-system use rate by children (odds ratio, 2.14; 95% CI, 1.12-4.06). Conclusion: Although the rate of safety-restraint-system use for children is increasing annually, it remains low. Additionally, the use rate of front passenger seats for children is high. To reduce the rates of injury and death of children from traffic accidents, it is necessary to educate on the appropriate use of safety restraint systems according to age and body size and to develop stronger regulations.