Logistatic Dose-response Models under Compliance Measurement Error for Some Problems in Inhalation Toxicology
نویسندگان
چکیده
MARIO CHEN MOK: Logistic Dose-Response Models under Compliance Measurement Error for some Problems in Inhalation Toxicology. (Under the direction ofDr. PRANAB KUMAR SEN.) In a classical measurement error model, true regressors, though unknown, vary stochastically around' the specified dose level. In inhalation toxicology problems, however, it is reasonable to assumed that the administered dose is not completely absorbed into the system because a portion of the dose is either metabolized or deflected by the different mechanisms in the body. This results in stochastic compliance of the administered dose, typically being smaller in magnitude. We introduce a model· for compliance based on a Beta distribution. Logistic models are among the most widely used models in dose-response analysis. In this research, we are primarily interested in stochastic compliance of various types, and the study of its impact on logistic models. We consider suitable adjustments for compliance of the administered doses, and develop appropriate approximate models that are likely to have reduced bias and more efficient statistical conclusions than in logistics models that ignore such measurement error. We develop compliance-adjusted models for the classical logistic model, a bivariate logistic model, and a segmented logistic model. These compliance-adjusted models are categorized into three types: (i) Low (or near zero) dose levels, (ii) moderate dose levels, and (iii) high dose levels. The low dose setting is appropriate 1II
منابع مشابه
Influence Measures in Ridge Linear Measurement Error Models
Usually the existence of influential observations is complicated by the presence of collinearity in linear measurement error models. However no method of influence measure available for the possible effect's that collinearity can have on the influence of an observation in such models. In this paper, a new type of ridge estimator based corrected likelihood function (REC) for linear measurement e...
متن کاملStochastic Restricted Two-Parameter Estimator in Linear Mixed Measurement Error Models
In this study, the stochastic restricted and unrestricted two-parameter estimators of fixed and random effects are investigated in the linear mixed measurement error models. For this purpose, the asymptotic properties and then the comparisons under the criterion of mean squared error matrix (MSEM) are derived. Furthermore, the proposed methods are used for estimating the biasing parameters. Fin...
متن کاملThe inhalation toxicology, genetic toxicology, and metabolism of difluoromethane in the rat.
Difluoromethane (HFC32) is under development as a replacement for chlorofluorocarbons (CFCs) in some refrigeration applications. It has been evaluated by standard studies of toxicity, developmental toxicity, and genotoxicity. In addition, the metabolism and disposition of HFC32 was investigated and a physiologically based pharmacokinetic (PB-PK) model constructed. Inhalation of HFC32 (up to 50,...
متن کاملEffective Dose Rate of Radon Gas in Jooshan Hot Spring of Kerman Province
Background & Aims: Human beings are constantly exposed to different radiations that have always been recognized as a health hazard. Radon -222 and its daughter products are major sources of natural radiations and a significant total inhalation dose is related to them. Hence, the measurement of radon activity in the environment has gained an increasing importance. In this study, with the measure...
متن کاملOverview of inhalation toxicology.
The development of inhalation toxicology as a distinct discipline can be traced back well over one hundred years. The technology has advanced in terms of materials and designs used to construct inhalation chambers and the equipment used to generate controlled test atmospheres of a wide variety of gases, vapors, dusts, and droplets. Consideration of metered dose inhalers, a relatively recent con...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1997