• Journal of the Korean Data and Information Science Society
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• 제22권3호
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• pp.605-612
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• 2011

In multi-center randomized clinical trial the treatment eect may be changed over centers. It is thus important to investigate the heterogeneity in treatment eect between centers. For this, uncorrelated random-eect models assuming independence between random-eect terms have been often used, which may be a strong assumption. In this paper we propose a correlated frailty modelling approach of investigating such heterogeneity using the hierarchical-likelihood method when the outcome is time-to-event. In particular, we show how to construct a proper prediction interval for frailty, which explores graphically the potential heterogeneity for a treatment-by-center interaction term. The proposed method is illustrated via numerical studies based on data from the design of a multi-center clinical trial.

• Communications for Statistical Applications and Methods
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• 제5권3호
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• pp.707-722
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• 1998

This paper evaluates a new clinical trial designs for low infection rate disease. This type of sparse disease reaction makes the traditional two sample t-test or Wilcoxon rank-sum test inefficient compared to a new test suggested. The new test, which is based solely on the larger changes, is shown to be more effective than existing method by simulation for small samples. However, this test can be shown to be connected to the locally most powerful rank test under certain practical conditions. This design is motivated in testing the treatment effects in periodontal disease research.

• 한방비만학회지
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• 제12권1호
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• pp.48-58
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• 2012

Objectives These prescribing recommendations have been written to guide clinicians on the appropriate use of Bangpungtongseong-san(BT) and Bangkihwangki-tang(BH) in the treatment of obesity. These recommendation are aimed at providing evidence based information concerning diagnosis and management of obesity. Methods We collected all relevant references about treatment effect of BT and BH on obesity in the forms of meta-analysis, systematic review, randomized controlled trial, case-control study, observational study and practice guideline from international and domestic databases and paper journals. We examined treatment effect, side effects, recommendations for dose, indication and contraindication of BT and BH. Results The treatment effect of BT and BH on obesity has been proved through clinical trial. BT is indicated for obese patients (Body mass index, $BMI{\geq}25$) with strong abdomen and a tendency to constipation, BH is indicated for obese patients ($BMI{\geq}25$) with a fair skinned, soft muscled, edematous and sweat easily. Conclusion We wish the information contained in theses recommendations will help clinicians reach a reasonable and beneficial decision with evidence-based results. Further studies are strongly needed to develop better treatment strategies for herbal medicines on obesity.

• 대한한방부인과학회지
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• 제24권3호
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• pp.171-189
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• 2011

Objectives: Female Sexual Dysfuction(FSD) is a common gynecologic condition and its prevalence is more higher than men. Despite its high prevalence and clinical importance, research on FSD is not enough in both of oriental and western medicine. The purpose of this study is to review research tendency of recent oriental medicine studies on FSD and to suggest the following research on FSD. Methods: We searched oriental medicine papers related to FSD published in the last 10 years(2001-2011) through Korean Medicine Gynecology Society database, KISS, RISS, NDSL, CNKI(China National Knowledge Infrastructure), and Pubmed. Results: 26 papers were searched, then 18 papers of them were related to Traditional Chinese Medicine(TCM), 8 papers of them were related to Korean Medicine(KM). In classification according to paper type, 16 papers were clinical study, 1 paper was experimental study, 2 papers were bibliographic study, and 7 papers were the other study. Then 5 papers of clinical study was Randomized Controlled Trial(RCT). Conclusion: There was a lack of oriental medicine research on FSD. On the base of this study, so further research is needed. Especially, Clinical trials such as RCT have strong objective evidence power in the viewpoint of Evidence Based Medicine(EBM) are needed.

• Communications for Statistical Applications and Methods
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• 제18권5호
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• pp.581-594
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• 2011

제 1상 임상시험 계획에서 신약제의 최대허용용량을 추정하기 위해 전통적 방법인 표준 3+3계획과 모형중심의 베이지안 방법을 적용시킨 연속재평가방법이 주로 사용되고 있다. 본 논문에서는 치료불응 또는 재발된 백혈병이나 골수형성 이상증후군 환자를 대상으로 시행한 제 1상 임상시험의 연구계획을 개관하였다. 단순한 표준 3+3계획으로 환자확보 기간이 길어져 연구를 완성하지 못하고 때 이르게 중단할 수밖에 없는 실정에 반하여, 최근에 제시된 표준 3+1+1계획과 Rolling-6 계획은 연구기간을 크게 단축시킬 수 있다. 제1상 임상시험의 용량수준 선택과정에서 너무 보수적인 연구자의 태도는 최대허용용량의 정확한 추정을 불가능하게 한다. 새로운 환자에게 투여할 용량수준을 결정할 시점에서 용량제한 독성반응이 아직 나타나지 않은 환자의 관측시간 및 늦게 나타나는 환자의 독성반응 시간을 모두 감안한 연속재평가방법인 TITE-CRM계획이 유용하며, 이러한 CRM계획으로 진행되는 임상시험 시행 중 모의실험으로 각 용량수준에서 용량제한 독성반응율이 과대 또는 과소 추정되는지를 파악할 수 있음이 장점이다. 백혈병환자 대상의 임상연구에서 채택되는 제 1상 임상시험의 여러 연구계획의 장, 단점을 제시한다.

• Communications for Statistical Applications and Methods
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• 제22권4호
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• pp.389-399
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• 2015

It is important not to overcalculate sample sizes for clinical trials due to economic, ethical, and scientific reasons. Kang and Kim (2014) investigated the accuracy of a well-known sample size calculation formula based on the approximate power for continuous endpoints in equivalence trials, which has been widely used for Development of Biosimilar Products. They concluded that this formula is overly conservative and that sample size should be calculated based on an exact power. This paper extends these results to binary endpoints for three popular metrics: the risk difference, the log of the relative risk, and the log of the odds ratio. We conclude that the sample size formulae based on the approximate power for binary endpoints in equivalence trials are overly conservative. In many cases, sample sizes to achieve 80% power based on approximate powers have 90% exact power. We propose that sample size should be computed numerically based on the exact power.

• Communications for Statistical Applications and Methods
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• 제15권5호
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• pp.727-735
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• 2008

Consider a clinical trial in which the main end-point is survival. Suppose after the start of the study an intermediate event occurs which may be influenced by a covariate(or treatment). In many clinical studies the occurrence of an intermediate event may change the survival distribution. This investigation develops two-stage model which, in the first stage, models the effect of covariate on the intermediate event and models the relationship between survival time and covariate as well as the intermediate event. In this paper, the two-stage model is presented in order to model intermediate event and a test based on this model is also provided. A numerical simulations are carried out to evaluate its overall significance level.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3284-3288
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• 2013

This paper describes first development and validation of pentafluorophenylprophyl ligand-based liquid chromatography coupled to tandem mass spectrometry (PFPLC-MS/MS) method to determine metformin, a highly polar compound, in human plasma. Metformin and Phenformin (internal standard) were extracted from human plasma 50 ${\mu}L$ with a single-step protein precipitation. The chromatographic separation was performed using a linear gradient elution of mobile phase involving 5.0 mM ammonium formate solution with 0.1% formic acid (A) and acetonitrile (B) over 3.0 min of run time on a Phenomenex Luna PFP column. The detection was performed using a triple-quadrupole tandem mass spectrometer (Waters Quattro micro) with electrospray ionization in the mode of positive ionization and multiple-reaction monitoring (MRM). The developed method was validated with 5.0 ng/mL of lower limit of quantification (LLOQ). The calibration curve was linear over 5-3000 ng/mL of the concentration range ($R^2$ > 0.99). The specificity, selectivity, carry-over effect, precision, accuracy and stability of the method met the acceptance criteria. The method developed in this study had had rapidness, simplicity and ruggedness. The reliable method was successfully applied to high throughput analysis of real samples for a practical purpose of a pharmacokinetic study.

• 대한한의학회지
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• 제44권2호
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• pp.70-105
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• 2023

This study was conducted to examine the current status of traditional korean medicine studies on gastroesophageal reflux disease in Korea, identify deficiencies, and suggest the direction of future medicine research methods to lay the foundation for traditional korean medicine treatment. All domestic papers on the korean traditional treatment of gastroesophageal reflux disease were selected among the literature published until August 2022 in six domestic databases. A total of 52 selected research data were classified into experimental research papers, clinical research papers, and review papers. In experimental papers, to evaluate the effectiveness of treatment, improvement of esophageal mucosal lesions, anti-inflammatory mechanisms, antioxidant mechanisms, esophageal mucosal protection mechanisms, gastric peristalsis control, and gastric acid secretion inhibition mechanisms were used as evaluation measures. In the clinical research paper, the basis for diagnosis of cases was clinical symptoms through medical history listening and diagnosis through visits to hospitals in the past. The average treatment period was 40.7 days, and the duration of treatment was not significantly affected by the duration of the disease. The most widely used Korean medicine treatment intervention was herbal medicine. There were 3 literature review studies, 3 systematic literature review and meta-analysis studies, 1 comparative review study for clinical trial guideline development, all using Chinese papers. This study included all domestic papers on gastroesophageal reflux disease to identify the research trend of the Korean oriental medicine community, and based on this, it is meaningful to confirm areas that need to be supplemented in future research plans.

• 한국컴퓨터정보학회논문지
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• 제15권1호
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• pp.23-30
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• 2010

의료 분야의 정보화와 다양화로 인해 한의학 분야에서도 지능화된 서비스를 제공해주는 온톨로지 기반의 지능형 의료 시스템에 관한 연구가 진행되고 있다. 지능형 의료 시스템은 온톨로지를 이용하여 복잡한 의료지식 및 개인의 의료정보등을구조화함으로써진단을과학화시키고보다나은의료서비스를제공하게해준다. 본 논문에서는 온톨로지를 이용하여 기본적인 의학 데이터, 진단 시 발생되는 임상데이터, 개인의 신체정보와 같은 세 가지 지식을 표현하여 온톨로지로 구축함으로써 개인 맞춤형 진단을 내리는데 중요한 데이터로 활용한다. 특히, 한의학진단에서는 환자 개인의 병증과 체질 등에 따라 상이한 진단 및 처방이 내려질 수 있기 때문에 개개인의 신체정보 및 질병 정보를 이용하여 사용자의 상황에 맞는 맞춤형의 진단 및 처방 서비스를 제공 해주는 지능형 진단보조시스템이 유용하다. 따라서 본 논문에서는 환자 개개인에게 맞춤형의 진단 서비스를 제공하기 위한 방법으로 개인의 신체정보 및 질병정보를 이용하여 한의학 온톨로지를 구축하고, 추론을 통해 진단을 내리는 한의학 진단보조시스템을 구현하였다.