Biomedical subjects

Siu-Keung Tse

Publications and source records attributed to Siu-Keung Tse.

4 recordsLinked to original sources

PubMed2006

Statistical quality control process for traditional Chinese medicine.

The statistical quality control process on raw materials and/or the final product of traditional Chinese medicine (TCM) is examined. We develop a statistical quality control (QC) method to assess a proposed consistency index of raw materials from different sources and/or final products manufactured at different sites. The idea is to construct a 95% confidence interval for a proposed consistency index under a sampling plan. If the constructed 95% confidence lower limit is greater than a prespecified QC lower limit, then we claim that the raw material or final products have passed the QC and hence can be released for further processing or use; otherwise, the raw materials and/or final product should be rejected. For a given component (the most active component if possible), a sampling plan is derived to ensure that there is a desired probability for establishing consistency between sites when there is truly no difference in raw materials or final products between sites. An example concerning the development of a TCM is presented to illustrate the proposed statistical QC method for assessing consistency in raw materials from two sites.

Algorithms↗

PubMed2003

Interval estimation for Weibull-distributed life data under Type II progressive censoring with random removals.

This paper explores the problem of interval estimation for parameters of Weibull-distributed data, which are Type II progressively censored with random removals. Seven different confidence interval-estimation procedures are considered. Four of them are based on a parametric bootstrapping approach. Others are based on the asymptotic normality method and the likelihood ratio statistic. We conduct a Monte Carlo simulation to evaluate the performance of these procedures based on their lengths and their coverage probabilities. Furthermore, an example is presented to illustrate the application of these procedures.

Animals↗

PubMed2003

Efficacy evaluation under type II censored plan with postclassified samples.

The main theme of this paper is efficacy evaluation under Type II censoring. Observations from a clinical trial are often postclassified into two groups in an effort to properly assess the efficacy of an intervention on each group. Thus, the numbers of observed lifetimes in the two groups are random outcomes. Parameter estimation and hypotheses testing under this postclassified setting are discussed. A numerical study is conducted to assess whether the results derived based on fixed sample sizes could be used in the postclassified case. The results would provide insight to practitioners in analyzing data observed under the postclassified case.

Clinical Trials as Topic↗

PubMed2002

Design and analysis of survival data under an integrated type-II interval censoring scheme.

This article considers the planning of Type-II interval censored life tests for exponentially distributed lifetimes. In particular, we explore two criteria that are based on the minimization of the asymptotic variance of maximum likelihood estimator of the model parameter and the associated cost of the experiment. A numerical study is conducted to evaluate the "optimal" plans based on these two criteria. The results of this study should provide practitioners useful insight in planning a Type-II interval censoring life test.

Algorithms↗