• Korea journal of population studies
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• v.9 no.1
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• pp.41-53
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• 1986

The purpose of this paper is two-fold. One is to investigate the determinants of the demand supply of labor, and another is to project long-term demand and supply of labor. The paper consists of three parts. In the first part, theoretical models and important hypotheses are discussed: for the case of a labor supply model, issues regarding discouraged worker model, permanent wage hypothesis, and relative wage hypothesis are examined and for the case of a demand model, issues regarding estimating an employment demand equation within the framework of an inverted short-run produc- tion function are inspected. Particularly, a theoretical justification for introducing a demographic cohort variable in a labor supply equation is also investigated. In the second part, empirical results of the estimated supply and demand equations are analyzed. Supply equations are specified differently between primary and secondary labor force. That is, for the case of primary labor force groups including males aged 25 and over, attempts are made to explain the variations in participation behavior within the framework of a neo-classical economics oriented permanent wage hypothesis. On the other hand, for the case of females and young male labor force, variations in participation rates are explained in terms of a relative wage hypothesis. In other words, the participation behavior of primary labor force is related to short-rum business fluctuations, while that of secondary labor force is associated with intermediate swings of business cycles and demographic changes in the age structure of population. Some major findings arc summarized as follows. (1) For the case of males aged 14~19 and 2O~24 groups and females aged 14∼19, the effect of schhool enrollment rate is dominant and thus it plays a key role in explaining the recent declining trend of participation rates of these groups. (2) Except for females aged 20∼24, a demographic cohort variable, which captures the impact of changes in the age structure on participation behavior, turns out to show positive and significant coefficients for secondary labor force groups. (3) A cyclical variable produce significant coefficients for prime-age males and females reflecting that as compared to other groups the labor supply behavior of these groups is more closely related to short-run cyclical variations (4) The wage variable, which represents a labor-leisure trade-off turns out to yield significant coefficients only for older age groups (6O and over) for both males and females. This result reveals that unlike the experiences of other higer-income nations, the participation decision of the labor force of our nation is not highly sensitive with respect to wage changes. (5)The estimated result of the employment demand equation displays that given that the level of GNP remains constant the ability of the economy to absord labor force has been declining;that is, the elasticity of GNP with respect to labor absorption decreasre over time. In the third part, the results of long-term projections (for the period of 1986 and 1995) for age-sex specific participation rates are discussed. The participation rate of total males is anticipated to increase slightly, which is contrary to the recent trend of declining participation rates of this group. For the groups aged 25 and below, the participation rates are forecast to decline although the magnitude of decrease is likely to shrink. On the other hand, the participation rate of prime- age males (25 to 59 years old) is predicted to increase slightly during 1985 and 1990. For the case of females, except for 20∼24 and 25∼34 age groups, the participation rates are projected to decrease: the participation rates of 25∼34 age group is likely to remain at its current level, while the participation rate of 20∼24 age group is expected to increase considerably in the future (specifi- cally, from 55% in 1985 to 61% in 1990 and to 69% in 1995). In conclusion, while the number of an excess supply of labor will increase in absolute magnitude, its size as a ratio of total labor force is not likely to increase. However, the age composition of labor force is predicted to change; that is, the proportion of prime-age male and female labor force is projected to increase.

• Tuberculosis and Respiratory Diseases
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• v.87 no.2
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• pp.185-193
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• 2024

Background: The mechanisms leading to lung fibrosis are still under investigation. This study aimed to demonstrate whether antacids could prevent the development of interstitial lung disease (ILD). Methods: This population-based longitudinal cohort study was conducted between January 2006 and December 2010 in South Korea. Eligible subjects were ≥40 years of age, exposed to proton pump inhibitors (PPI)±histamine-2 receptor antagonists (H-2 blockers) or H-2 blockers only, and had no history of ILD between 2004 and 2005. Exposure to antacids was defined as the administration of either PPI or H-2 receptor antagonists for >14 days, whereas underexposure was defined as antacid treatment administered for less than 14 days. Newly developed ILDs, including idiopathic pulmonary fibrosis (IPF), were counted during the 5-year observation period. The association between antacid exposure and ILD development was evaluated using adjusted Cox regression models with variables, such as age, sex, smoking history, and comorbidities. Results: The incidence rates of ILD with/without antacid use were 43.2 and 33.8/100,000 person-years, respectively and those of IPF were 14.9 and 22.9/100,000 person-years, respectively. In multivariable analysis, exposure to antacid before the diagnosis of ILD was independently associated with a reduced development of ILD (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.45 to 0.71; p<0.001), while antacid exposure was not associated with development of IPF (HR, 0.88; 95% CI, 0.72 to 1.09; p=0.06). Conclusion: Antacid exposure may be independently associated with a decreased risk of ILD development.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2513-2518
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• 2016

Background: In 2008, non-Hodgkin lymphoma ranked tenth among other malignancies worldwide with an incidence of around 5 cases per 100,000 in both genders. The latest available rates in Tunisia are from 2006. Materials and Methods: This study aimed to provide an update about NHL incidence for 2009 and its trend between 1998 and 2009 as well as a projection until 2024, using data from the Salah Azaiz Institute hospital registry and the Noth Tunisia cancer registry. Results: In 2009, the NHL incidence in the north of Tunisia was 4.03 cases per 100,000, 4.97 for men and 3.10 for women. Diffuse large B-cell lymphoma (DLBCL) accounted for 63.2% of all NHL subtypes. Between 1998 and 2009, the overall trend showed no significant change. When we compared the trend between two periods (1998-2005 and 2005-2009), joinpoint regression showed a significant decrease of NHL incidence in the first period with an annual percentage change (APC) of -6.7% (95% CI:[-11.2%;-2%]), then the incidence significantly increased from 2005 to 2009 with an APC of 30.5% (95% CI: [16.1%; 46.6%]. The analyses of the different subtype trends showed a significant decrease in DLBCL incidence between 1998 and 2000 (APC:-21.5; 95% CI: [-31.4%;-10.2%]) then the incidence significantly increased between 2004 and 2007 (APC: 18.5; 95% CI: [3,6%;35.5%]). Joint point analysis of the age-period-cohort model projection showed a significant increase between 2002 and 2024 with an APC of 4.5% (%95 CI: [1.5%; 7.5%]). The estimated ASR for 2024 was 4.55/100 000 (95% CI: [3.37; 6.15]). Conclusions: This study revealed an overall steady trend in the incidence of NHL in northern Tunisia between 1998 and 2009. Projection showed an increase in the incidence in NHL in both genders which draw the attention to the national and worldwide burden of this malignancy.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1905-1909
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• 2013

Objective: The aim of the current study was to evaluate changes in treatment outcomes in terms of health-related quality of life (HRQoL) and symptom burden at zero, one, three, and six months after an initial diagnosis of colorectal cancer. The demographic and clinical characteristics that account for outcome changes in patients were investigated using a repeated measures framework. Methods and Materials: A cohort study was performed of 134 colorectal cancer patients followed from diagnosis to 6 months post-treatment in Central Taiwan. HRQoL and symptoms were assessed at diagnosis and one, three, and six months thereafter. The Functional Assessment of Cancer Therapy-Colon (FACT-C) questionnaire, VAS pain, and the Memorial Symptom Assessment Scale (MSAS) were used for data collection. A generalized estimating equation (GEE) was applied for statistical analysis. Results: The majority of the patients were male (55%) and married (91.5%). The mean age was 60.4 years (SD = 11.71). Most were diagnosed stage III and IV colorectal cancer (54.5%). All underwent surgery; some also received chemotherapy (CT) or concurrent chemoradiation therapy (CCRT). The results of the GEE showed that overall, the HRQoL, pain, and symptoms of the patients significantly improved over the treatment period. Patients with stage IV disease who had received surgery and CCRT showed the worst HRQoL. Females, patients with comorbidity, and stage IV patients had higher pain scores over time. Female and stage IV patients had more severe physical symptoms, whereas stage II and IV patients had worse psychological symptoms over time. Conclusion: The patients' HRQoL, pain, and symptoms significantly improved over the 6-month treatment period. Certain patient and clinical variables accounted for changes in treatment outcomes regarding HRQoL and symptom burden in colorectal cancer patients.

• The Korean journal of internal medicine
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• v.39 no.4
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• pp.612-624
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• 2024

Background/Aims: The predictive value of the estimated pulse wave velocity (ePWV) for the development of metabolic syndrome has not yet been extensively explored. This study aimed to fill this gap by evaluating ePWV as a potential predictor of metabolic syndrome development in middle-aged Korean adults. Methods: Using prospective data obtained from the Ansan-Ansung cohort database, participants without metabolic syndrome at baseline were studied. ePWV was calculated using specific equations based on age and blood pressure. The primary outcome was the incidence of metabolic syndrome during a median follow-up period of 187 months. Results: Among the 6,186 participants, 2,726 (44.1%) developed metabolic syndrome during the follow-up period. ePWV values were categorized into tertiles to assess their predictive value for the development of metabolic syndrome. An ePWV cut-off of 7.407 m/s was identified as a predictor of metabolic syndrome development, with a sensitivity of 0.743 and a specificity of 0.464. Participants exceeding this cut-off, especially those in the third tertile (8.77-14.63 m/s), had a notably higher risk of developing metabolic syndrome. Specifically, the third tertile exhibited a 52.8% cumulative incidence compared with 30.8% in the first tertile. After adjustments, those in the third tertile faced a 1.530-fold increased risk of metabolic syndrome (95% confidence interval, 1.330-1.761). Conclusions: ePWV is a significant predictor of the development of metabolic syndrome. This finding underscores the potential of ePWV as a cardiometabolic risk assessment tool and can thus provide useful information for primary prevention strategies.

• Journal of Preventive Medicine and Public Health
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• v.34 no.2
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• pp.157-165
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• 2001

Objectives : To identify the risk factors of cerebrovascular disorders(CVD) in Koreans using a nested case-control study. Methods : The cohort consisted of beneficiaries who had taken health examinations of the Korea Medical Insurance Corporation (KMIC cohort: 115,600 persons) in 1990 and 1992 consecutively. Four hundred and twenty five (425) cases were selected following the validation of diagnosis among 2,026 reported CVD (160-168) inpatients during the year from 1993 to 1997. Controls were matched (1:1) with age and gender of the cases among inpatients without CVD during the same period. The source of data in this study were the files of the 1990 health examinations and the 1992 health questionnaires, as well as an additional telephone survey undertaken from March to November 1999. Results : In a bivariate analysis and multiple logistic regression analysis, risk factors for total CVD were hyperglycemia and hypertension. Unrespectively, the odds ratio of ex-smoker was significantly lower than that of those who had never smoked. The risk factors for ischemic CVD also were hyperglycemia and hypertension. However, only blood pressure was found to be a risk factor for hemorrhagic CVD. Hypercholesterolemia was not a risk factor for total CVD, ischemic CVD, and hemorrhagic CVD. Conclusion : We concluded that the most important risk factor for CVD (including subtype) in Koreans was hypertension.

• Clinical and Experimental Pediatrics
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• v.53 no.11
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• pp.965-970
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• 2010

Purpose: The life expectancy of patients with spinal muscular atrophy (SMA) type I is generally considered to be less than 2 years. Recently, with the introduction of proactive treatments, a longer survival and an improved survival rate have been reported. In this study, we analyzed the natural courses and survival statistics of SMA type I patients and compared the clinical characteristics of the patients based on their survival periods. Methods: We reviewed the medical records of 14 pediatric patients diagnosed with SMA type I during a 9-year period. We examined the demographic and clinical characteristics of these patients, calculated their survival probabilities, and plotted survival curves as on the censoring date, January 1, 2010. We also compared the characteristics of the patients who died before the age of 24 months (early-death, ED group) and those who survived for 24 months or longer (long-survival, LS group). Results: The mean survival time was $22.8{\pm}2.0$ months. The survival probabilities at 6 months, 12 months, 18 months, 24 months, and 30 months were 92.9%, 92.9%, 76.0%, 76.0%, and 65.1%, respectively. Birth weight was the only factor that showed a statistically significant difference between the ED and LS groups ($P$=0.048). Conclusion: In this study, the survival probabilities at 2 years were far greater than expected. Because of the limited number of patients and information in this study, the contribution of improved supportive care on longer survival could not be clarified; this may be elucidated in larger cohort studies.

• Journal of muscle and joint health
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• v.29 no.1
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• pp.41-49
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• 2022

Purpose: The purpose of this study was to assess the influence of nurses staffing level on patient health outcomes in intensive care units (ICUs) in Korea. Methods: The study was retrospective in nature. Information on patients and their outcomes, as well as nurse cohort data, were obtained from Korea's National Health Insurance Service Database. The observation period was from January 1, 2008 to December 31, 2018, and data for 2,964,991 patients were analyzed. Independent variables included patient' age and sex and hospital type, intensivist, and nurses staffing level. Results: The mortality rate in ICUs was significantly higher at tertiary hospitals with a level 3~4 (HR, 1.21; 95% confidence interval, 1.19~1.22) or level 5~9 nurse staffing (HR, 1.31; 95% confidence interval, 1.27~1.34) compare to that of tertiary hospitals with a 1~2 level. 28-day mortality rate was also higher at general hospitals with a level 3~4 (HR, 1.13; 95% confidence interval, 1.12~1.14), level 5~6 (HR. 1.34; 95% confidence interval, 1.32~1.36), level 7~9 nurse staffing (HR, 1.38; 95% confidence interval, 1.38~1.42), using level 1~2 as reference. Conclusion: Nurses staffing level is a key determinant of healthcare-associated mortality in critically ICUs patients. Policies to achieve adequate nurse staffing levels are therefore required to enhance patient outcomes.

• Journal of The Korean Society of Clinical Toxicology
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• v.18 no.2
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• pp.57-65
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• 2020

Purpose: Since 2012, acetaminophen can be accessed easily not only at pharmacies but also at convenience stores. The relationship between the easy access of acetaminophen and the risk of poisoning has been controversial. Several studies also reported different results regarding the risk of acetaminophen poisoning after access to acetaminophen was relaxed. This study examined the long-term effects on the risk of acetaminophen poisoning after easy access to acetaminophen was implemented. Methods: This was a retrospective analysis of an emergency department (ED)-based in-depth Injury Surveillance Cohort by the Korea Center for Disease Control and prevention from 2011 to 2018. Poisoning cases were selected from the Cohort, and the incidence of acetaminophen poisoning and the characteristics of the cases of acetaminophen poisoning were analyzed. The purchase path and the amount of ingestion in acetaminophen poisoning were sub-analyzed from data of six EDs. Results: Of 57,326 poisoning cases, 4.0% (2,272 cases) were acetaminophen poisoning. Of 2,272 cases of acetaminophen poisoning, 42.8% (974 cases) required in-patient care after ED management. Two hundred and sixty-four of these 964 cases required intensive care. The rates of cases that required in-patient treatment and the rates of cases that required intensive care increased from 29.4% in 2011 to 48.1% in 2018, and from 3.1% in 2011 to 15.2% in 2018, respectively (p<0.001, p<0.001). In the poisoning group with in-depth toxic surveillance (n=15,908), the incidence and proportion of acetaminophen (AAP) poisoning increased from 55 cases per year to 187 cases per year and 4.9% to 6.1%, respectively (p=0.009, p<0.001, respectively). The most common age group of acetaminophen poisoning was teenagers, which is different from the most common age group of other pharmaceutical agents: the middle age group of 40-49 years (p<0.001). Of 15,908 in-depth toxic surveillance patients, 693 patients had AAP poisoning, of whom 377 cases (54.2%) purchased acetaminophen from a non-pharmacy. The proportions of the purchase path from non-pharmacy were 41.4% at 2011-12 and 56.4% (2013-18) (p=0.004). The amount of acetaminophen ingestion was 13.5±14.3 g at 2011-12 and 13.9±15.1 g at 2013-18 (p=0.794). Conclusion: Although the incidence of acetaminophen poisoning did not increase remarkably in the short term after the implementation of the new regulation, the incidence of acetaminophen poisoning has increased slightly during the study period of 2017-18. In addition, the proportion of the purchase path from non-pharmacies has increased since the emergence of new regulations for the easy access of acetaminophen in 2012. The incidence of acetaminophen poisoning might have been affected after the increasing accessibility of acetaminophen in convenience stores. Continuous control of acetaminophen poisoning is required. Furthermore, the prevention of acetaminophen poisoning should be focused on teenagers with specialized school education programs.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.25-35
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• 1999

Background : The treatment for multi-drug resistant tuberculosis(MDRTB) is encountered to be important clinically, but there are still a few reports about it all over the world. So, we evaluated the outcomes of only chemotherapy for the pulmonary MDRTB retrospectively. Method: We reviewed the clinical courses of 63 patients with pulmonary disease due to M.tuberculosis resistant to rifampin and isoniazid who were under follow-up between March 1996 and June 1996 after hospitalization at our hospital between January 1993 and January 1996. We performed cohort retrospective study for all these patient's records. Their regimens were selected individually and preferably included four medications that they had not been given previously and to which the strain was fully susceptible. Results: The 63 patients(mean age, 43.2 years) had previously received a median 5.1drugs. Fifty two(82.5%) patients responded to chemotherapy(as indicated by negative sputum cultures for at least three consecutive months) ; eleven patients(17.5 %) had no response, as shown by continually positive cultures. In a univariate analysis, an unfavorable response was significantly associated with greater number of resistant drugs before the current courses of therapy(relative risk 21.5 ; 95 percent confidence interval, 1.2-3.0; p<0.05). The mean period of follow-up was seventeen months. There was no relapse suooequently among the patients with responses. There was no death related to tuberculosis. Conclusion: In this report from National Masan Tuberculosis Hospital in Korea, multi-drug resistant pulmonary tuberculosis responded relatively well to carefully selected regimens.