• The Korean Journal of Applied Statistics
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• v.21 no.5
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• pp.739-754
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• 2008

Researches on conversion formulas between multiple decrement models and the associated single decrement models have focused on calculating yearly-based conversion formulas. In practice, actuaries may be more interested in monthly-based conversion formulas. Multiple decrement tables and their associated single decrement tables consist of yearly-based rates of multiple decrements and absolute rates of decrements, respectively. This paper derives conversion formulas from yearly-based absolute rates of decrements to monthly-based rates of decrement due to cause j under the uniform distribution of decrements(UDD). Next, it suggests conversion formulas from monthly-based absolute rates of decrements to monthly-based rates of decrement due to cause j under UDD. In addition, it calculates conversion formulas from yearly-based rates of decrement due to cause j to the corresponding absolute rates of decrements under UDD or constant force assumption. Some numerical examples are discussed.

• The Korean Journal of Applied Statistics
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• v.26 no.3
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• pp.549-568
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• 2013

This paper discusses conversion methods between multiple decrement models and associated single decrement models. One of most popular assumptions on fractional age is UDD(uniform distribution of decrement) or constant force of mortality in actuarial practice. Instead of these assumptions, this paper suggests cubic spline interpolation to approximate the distribution of fractional age with the continuous force of decrements. Conversion formulas are derived. The comparisons of these two methods based on the numerical data show that the cubic spline interpolation approach is more accurate.

• Korean Journal of Clinical Laboratory Science
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• v.38 no.1
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• pp.1-8
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• 2006

The purposes of this study were to evaluate the changes in hematologic indices after plateletpheresis and to identify the preapheresis platelet count and clinical factors (age, gender, height, and weight) that showed some influence on the percentage of platelet decrement, yield and efficiency. Plateletpheresis was performed on 101 healthy donors in Bundang CHA general hospital. The data was analyzed using the SAS program with t-test, ANOVA test and Multiple regression. The mean percentage decrease after plateletpheresis was 2.0% in hemoglobin, 1.8% in hematocrit, and 29.7% in the platelet count, while a WBC count showed an increase of 2.6%. The mean percentage decrease of hemoglobin and hematocrit were 1.7% and 1.4%, in males and 3.6% and 3.7% in females, respectively. Particularly the percentage decrease of platelet count was significantly higher in females (40.0%) than in males (27.2%). The platelet decrementage and yield were significantly higher in females, but the efficiency did not differ significantly between males and females. The yield showed the lowest levels in subjects who were 40 years old or over but the platelet decrement and efficiency did not change according to age. The platelet decrement increased as height and weight increased. Also, the platelet decrement and yield increased as the initial platelet counts increased, but the efficiency did not. From multiple regression analysis, the platelet decrement was associated with gender, weight, and initial platelet count. The yield was related to the initial platelet count, but the efficiency was not related to gender, age, weight, height or initial platelet counts. This study has a limitation of the generality of the study results since this study was conducted only in a single university hospital. Further study would be necessary to find out a subpopulation that is sensitive to the hematologic change after plateletpheresis, and to determine the standard criteria for blood donation based on the subpopulation.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.17 no.1
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• pp.31-36
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• 2014

Purpose: Infliximab (IFX) is considered safe and effective for the treatment of ulcerative colitis (UC) in both adults and children. The aim of this study was to evaluate the short- and long-term clinical course of IFX in Korean children with UC. Methods: Pediatric patients with UC who had received IFX infusions between November 2007 and May 2013 at Samsung Medical Center were retrospectively investigated. The clinical efficacy of IFX treatment was evaluated at 8 weeks (short term) and 54 weeks (long term) after the initiation of IFX treatment using the Pediatric Ulcerative Colitis Activity Index (PUCAI). The degree of response to IFX treatment was defined as complete response (PUCAI score=0), partial response (decrement of PUCAI score${\geq}20$ points), and non-response (decrement of PUCAI score <20 points). Adverse events associated with IFX treatment were also investigated. Results: Eleven pediatric patients with moderate to severe UC had received IFX. The remission rate after IFX treatment was 46% (5/11) and 82% (9/11) at 8 weeks and 54 weeks after IFX treatment, respectively. All patients who were steroid-dependent before treatment with IFX achieved remission at 54 weeks and were able to stop treatment with corticosteroids, while all steroid-refractory patients failed to achieve remission at 54 weeks after treatment with IFX. Conclusion: Response to IFX treatment after 8 weeks may predict a favorable long-term response to IFX treatment in Korean pediatric UC patients.