• International Journal of Reliability and Applications
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• 제7권2호
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• pp.177-186
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• 2006

Typical confidence intervals for a mean or mean residual life (MRL) are centered about the mean or mean residual life. We discuss novel confidence intervals that produce statements like "we are 95% confident that the MRL function, e(t), is greater than a prespecified $\mu_o$ for all t in the interval [0, $\hat{\theta})$)" where $\hat{\theta}$ is determined from the sample data, confidence level, and $\mu_o$. Also, we can have statements like 'we are 95% confident that the MRL of population 1, namely $e_1$(t), is greater than the MRL of population 2, $e_2$(t), for all t in the interval [0, $\hat{\theta}$)" where $\hat{\theta}$ is determined from the sample data and confidence level. We illustrate these one and two sample confidence intervals on internal bonds (tensile strengths) for an important modem engineered wood product, called medium density fiberboard (MDF), used internationally.

• The Journal of Advanced Prosthodontics
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• 제9권4호
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• pp.287-293
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• 2017

PURPOSE. To compare the dimensional accuracy of three impression techniques- a separating foil impression, a custom tray impression, and a stock tray impression. MATERIALS AND METHODS. A machined mandibular complete-arch metal model with special modifications served as a master cast. Three different impression techniques (n = 6 in each group) were performed with addition-cured silicon materials: i) putty-wash technique with a prefabricated metal tray (MET) using putty and regular body, ii) single-phase impression with custom tray (CUS) using regular body material, and iii) two-stage technique with stock metal tray (SEP) using putty with a separating foil and regular body material. All impressions were poured with epoxy resin. Six different distances (four intra-abutment and two inter-abutment distances) were gauged on the metal master model and on the casts with a microscope in combination with calibrated measuring software. The differences of the evaluated distances between the reference and the three test groups were calculated and expressed as mean (${\pm}SD$). Additionally, the 95% confidence intervals were calculated and significant differences between the experimental groups were assumed when confidence intervals did not overlap. RESULTS. Dimensional changes compared to reference values varied between -74.01 and $32.57{\mu}m$ (MET), -78.86 and 30.84 (CUS), and between -92.20 and 30.98 (SEP). For the intra-abutment distances, no significant differences among the experimental groups were detected. CUS showed a significantly higher dimensional accuracy for the inter-abutment distances with -0.02 and -0.08 percentage deviation compared to MET and SEP. CONCLUSION. The separation foil technique is a simple alternative to the custom tray technique for single tooth restorations, while limitations may exist for extended restorations with multiple abutment teeth.

• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.372-377
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• 2014

Being able to monitor the heart will allow the diagnosis of heart diseases for patients during daily activities, and the detection of burden on the heart during strenuous exercise. Furthermore, with the help of U-health technology, immediate medical action can be taken, in the case of abnormal symptoms of the heart in daily life. Therefore, it appears to be necessary to develop the corresponding technology to monitor the condition of the heart daily. In this study, a novel wearable smart system was proposed, to monitor the activity of the heart in daily life, and to further evaluate the rhythm of arrhythmia. The wearable system includes three modified bipolar conductive fiber electrodes in the chest part, which can resolve the reduction problem of the magnitude of the signal, by magnifying the signal and removing the noise, to obtain high affinity and validity for medical-type usage (<0.903%). The biological signal acquisition and data lines, and the signal processing engine and communication consist of a conductive ink, and the pic18 and ANT protocol nRF24AP2, respectively. The proposed algorithm was able to detect a strong ECG, signal and r-point passing over the noise. The confidence intervals were 96 %, which could satisfy the requirement to detect arrhythmia under the unconstrained conditions.

• 한국임상약학회지
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• 제29권4호
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• pp.247-253
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• 2019

Background: Glutamate is implicated in the pathophysiology of migraine, a common neurological disorder. Therefore, glutamate receptor antagonists (GluRAs) have been suggested as a novel migraine treatment that are able to overcome the limitations of triptans. Objective: The aim of this study was to perform a meta-analysis to assess the efficacy of GluRAs for patients with migraine. Method: The PubMed, Cochrane Library, CINAHL, and Clinical Trial.gov databases were searched for randomized placebo-controlled trials of the efficacy of GluRAs for patients with migraine conducted up to August 2019. Two independent reviewers screened the literature according to inclusion and exclusion criteria and performed quality assessment and data extraction. Review Manager 5.3 software was used for the meta-analysis. Results: Three studies involving a total of 206 patients were included in the final analysis. Compared with placebo, GluRAs significantly improved the pain-free response at 2 hours (odds ratio [OR]=3.85, 95% confidence intervals [CIs]=1.63-9.09) and the 24-hour sustained pain freedom (OR=7.40; 95% CIs=2.36-23.20). The use of rescue medications with GluRAs was lower compared to that with placebo, but the difference was not significant (OR=0.39, 95% CI=0.10-1.47). Conclusion: Our meta-analysis showed that GluRAs were more effective than placebo for patients with migraine.

• Journal of Preventive Medicine and Public Health
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• 제57권5호
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• pp.499-507
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• 2024

Objectives: This study aimed to compare the Delta, Greenland, and Monte Carlo methods for estimating 95% confidence intervals (CIs) of the population-attributable fraction (PAF). The objectives were to identify the optimal method and to determine the influence of primary parameters on PAF calculations. Methods: A dataset was simulated using hypothetical values for primary parameters (population, relative risk [RR], prevalence, and variance of the beta estimator ) involved in PAF calculations. Three methods (Delta, Greenland, and Monte Carlo) were used to estimate the 95% CIs of the PAFs. Perturbation analysis was performed to assess the sensitivity of the PAF to changes in these parameters. An R Shiny application, the "GDM-PAF CI Explorer," was developed to facilitate the analysis and visualization of these computations. Results: No significant differences were observed among the 3 methods when both the RR and p-value were low. The Delta method performed well under conditions of low prevalence or minimal RR, while Greenland's method was effective in scenarios with high prevalence. Meanwhile, the Monte Carlo method calculated 95% CIs of PAFs that were stable overall, though it required intensive computational resources. In a novel approach that utilized perturbation for sensitivity analysis, was identified as the most influential parameter in the estimation of CIs. Conclusions: This study emphasizes the necessity of a careful approach for comparing 95% CI estimation methods for PAFs and selecting the method that best suits the context. It provides practical guidelines to researchers to increase the reliability and accuracy of epidemiological studies.

• 한국임상약학회지
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• 제33권4호
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• pp.290-304
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• 2023

Background: Innovative Alzheimer's disease drugs received approval in the United States in 2021 and 2023. This study aims to assess the safety and efficacy of these novel treatments, elucidate their mechanisms of action, and compare their impact on cognitive function improvement with approved drugs. Methods: We conducted a comprehensive search of pivotal clinical studies related to Alzheimer's disease treatments in PubMed/Medline, Embase, and the Cochrane Library databases from January 1st, 2020 to December 31st, 2022. Meta-analysis was performed using RevMan 5.4 software. Results: A total of 14 studies were included in this systematic review. When compared to the placebo, the new drugs did not exhibit a statistically significant effect on MMSE (Mini-Mental State Examination) (mean difference= -0.04, 95% confidence intervals [CIs]: -0.31, 0.23, N=3662, I²=0%). However, they demonstrated a significant impact on ADAS-cog (Alzheimer's Disease Assessment Scale-Cognitive Subscale) (standardized mean difference= -0.15, 95% CIs: -0.2, -0.1, N=6710, I²=17%). When compared to the approved drugs, the new drugs showed a statistically significantly lower effect on MMSE (test for subgroup difference Chi²=23.13, N = 5870, p<0.00001) but showed only a trend of decreased efficacy on ADAS-cog (Chi²=1.16, N = 8670, p=0.28). Conclusion: New drugs yielded diverse clinical endpoint results compared to the placebo, and in comparison to existing approved drugs, they exhibited lower efficacy in improving cognitive function. The safety profile of these new drugs, as reported in clinical trials, was generally well-tolerated.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10501-10504
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• 2015

Background: Colon cancer is the second most common cancer in developed countries. Activated platelets play a key role in inflammation and atherothrombosis, with mean platelet volume (MPV) is an early marker of platelet activation. The aim of the study was to clarify the relevance of MPV in patients with colon cancer. Materials and Methods: We measured MPV levels in 128 patients with colon cancer before and after surgery, and 128 controls matched for age, gender, body mass index (BMI) and smoking status. The odds ratios (ORs) and 95% confidence intervals (CIs) for colon cancer were calculated using multivariate logistic regression analyses across MPV quartiles. Results: Patients with colon cancer had higher MPV compared with controls. Surgical tumor resection resulted in a significant decrease in MPV levels (11.4 fL vs 10.7 fL; p<0.001). A positive correlation between MPV and tumor-nodule-metastases (TNM) stage was found. Furthermore, after adjusting for other risk factors, the ORs (95%CIs) for colon cancer according to MPV quartiles were 1.000, 2.238 (1.014-4.943), 3.410 (1.528-7.613), and 5.379 (2.372-12.198), respectively. Conclusions: The findings show that patients with colon cancer have higher MPV levels compared with controls, and these are reduced after surgery. In addition, MPV was found to be independently associated with the presence of colon cancer. Further studies are warranted to assess the utility of MPV as a novel diagnostic screening tool for colon cancer.

• The Korean Journal of Physiology and Pharmacology
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• 제26권3호
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• pp.195-205
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• 2022

Determining blood loss [100% - RBV (%)] is challenging in the management of haemorrhagic shock. We derived an equation estimating RBV (%) via serial haematocrits (Hct₁, Hct₂) by fixing infused crystalloid fluid volume (N) as [0.015 × body weight (g)]. Then, we validated it in vivo. Mathematically, the following estimation equation was derived: RBV (%) = 24k / [(Hct₁ / Hct₂) -1]. For validation, non-ongoing haemorrhagic shock was induced in Sprague-Dawley rats by withdrawing 20.0%-60.0% of their total blood volume (TBV) in 5.0% intervals (n = 9). Hct₁ was checked after 10 min and normal saline N cc was infused over 10 min. Hct₂ was checked five minutes later. We applied a linear equation to explain RBV (%) with 1 / [(Hct₁ / Hct₂) -1]. Seven rats losing 30.0%-60.0% of their TBV suffered shock persistently. For them, RBV (%) was updated as 5.67 / [(Hct₁ / Hct₂) -1] + 32.8 (95% confidence interval [CI] of the slope: 3.14-8.21, p = 0.002, R² = 0.87). On a Bland-Altman plot, the difference between the estimated and actual RBV was 0.00 ± 4.03%; the 95% CIs of the limits of agreements were included within the pre-determined criterion of validation (< 20%). For rats suffering from persistent, non-ongoing haemorrhagic shock, we derived and validated a simple equation estimating RBV (%). This enables the calculation of blood loss via information on serial haematocrits under a fixed N. Clinical validation is required before utilisation for emergency care of haemorrhagic shock.

• Journal of Pharmaceutical Investigation
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• 제31권2호
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• pp.125-130
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• 2001

Bucillamine is a novel cysteine derivative with two free intramolecular sulfhydryl groups, and has a preventive and therapeutic effect on adjuvant arthritis, suggesting its antirheumatic action. With respect to the effect on the immune system, bucillamine-exerted such immunoregulating actions are to nomalize an excessive reduction or acceleration in immune reaction. It is useful not only in patients with early stage of rheumatoid arthritis (RA) but also in those with active RA retained for more than 10 years. The purpose of the present study was to evaluate the bioequivalence of two bucillamine tablets, $Rimatil^{TM}$ (Chong Kun Dang Pharmaceutical Co., Ltd.) and $Bucilin^{TM}$ (Kuhn Il Pharmaceutical Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). Eighteen normal male volunteers, $23.67{\pm}2.09$ years in age and $65.03{\pm}6.73\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After three tablets containing 100 mg of bucillamine per tablet were orally administered, blood was taken at predetermined time intervals and the concentrations of bucillamine in serum were determined using GC/MS with mass selective detector. Pharmacokinetic parameters such as $AUC_t$, $C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t$, $C_{max}\;and\;T_{max}$ between two tablets were -0.29%, -3.20% and 8.22%, respectively, when calculated against the $Rimatil^{TM}$ tablet. The powers $(1-{\beta})$ for $AUC_t\;and\;C_{max}$ were 84.31 % and 91.16%, respectively. Minimum detectable differences $({\Delta})$ at ${\alpha}=0.10$ and $1-{\beta}=0.8$ were less than 20% (e.g., 18.58% and 16.51% for $AUC_t\;and\;C_{max}$, respectively). The 90% confidence intervals were within ${\pm}20%$ (e.g.,$-12.77{\sim}12.20$ for $AUC_t$ and $-14.30{\sim}7.90$ for $C_{max}$). Two parameters met the criteria of KFDA for bioequivalence, indicating that $Bucilin^{TM}$ tablet is bioequivalent to $Rimatil^{TM}$ tablet.

• Journal of Pharmaceutical Investigation
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• 제31권4호
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• pp.281-287
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• 2001

Rebamipide is a novel anti-gastric ulcer agent that has been reported to increase the synthesis of mucus, to increase the mucosal concentration of prostaglandin, and to promote rapid ulcer healing. The purpose of the present study was to evaluate the bioequivalence of two rebamipide tablets, $Mucosta^{TM}$ (Otsuka Korea Pharmaceutical Co., Ltd.) and $Rebamide^{TM}$ (Kyung Dong Pharmaceutical Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The rebamipide release from the two rebamipide tablets in vitro was tested using KP VII Apparatus II method at pH 6.8 dissolution media. Twenty normal male volunteers, $24.20{\pm}2.26$ years in age and $66.19{\pm}9.41\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 100 mg of rebamipide was orally administered, blood was taken at predetermined time intervals and the concentrations of rebamipide in serum were determined using HPLC method with fluorescence detector. The dissolution profiles of two rebamipide tablets were very similar at pH 6.8 dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t$, $C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t$, $C_{max}\;and\;T_{max}$ between two tablets based on the $Mucosta^{TM}$ were -2.57%, 5.77% and -1.47%, respectively. Minimum detectable differences $({\Delta})$ at ${\alpha}=0.05$ and $1-{\beta}=0.8$ were less than 20% (e.g., 12.62% and 17.63% for $AUC_t,\;and\;C_{max}$, respectively). The powers $(1-{\beta})$ at ${\alpha}=0.05$, ${\Delta}=0.2$ for $AUC_t\;and\;C_{max}$ were above 99.00% and 88.56%, respectively. The 90% confidence intervals were within ${\pm}20%$ (e.g., $-9.96{\sim}4.82$ and $-4.54{\sim}16.09$ for $AUC_t\;and\;C_{max}$, respectively). Two parameters met the criteria of KFDA for bioequivalence, indicating that $Rebamide^{TM}$ tablet is bioequivalent to $Mucosta^{TM}$ tablet.