Methods for estimating pharmaceutical shelf life based on tolerance intervals are proposed by Schwenke, et al. AAPS PharmSciTech. 2020;21:290, [1] where a critical quality attribute that follows a simple linear (straight line) response trend across storage time is presented as the traditional example.
View Article and Find Full Text PDFAAPS PharmSciTech
November 2021
This paper is a companion article to the research originally presented in "Estimating Shelf Life through Tolerance Intervals" (Schwenke et al., 21:290, 2020) published in AAPS PharmSciTech where tolerance intervals are introduced as an alternative methodology for estimating pharmaceutical shelf life. An industry stability shelf life example data set was used to demonstrate the proposed methods.
View Article and Find Full Text PDFThis paper is a continuation of the research published by the Stability Shelf Life Working Group as chartered under the Product Quality Research Institute. The Working Group was formed in 2006 and disbanded in late 2019. Following the philosophy presented by the Working Group on how to characterize the stability shelf life paradigm (Capen et al.
View Article and Find Full Text PDFIt is often of interest to predict spatially correlated count outcomes that follow a Poisson distribution. For example, in the environmental sciences we may want to predict pollen counts using temperature or precipitation data as auxiliary variables. To predict a Poisson outcome variable in the presence of an auxiliary variable, Poisson cokriging as a Generalized Linear Mixed Model (GLMM) is proposed.
View Article and Find Full Text PDFHybrid wheat (Triticum spp.) has the potential to boost yields and enhance production under changing climates to feed the growing global population. Production of hybrid wheat seed relies on male sterility, the blocking of pollen production, to prevent self-pollination.
View Article and Find Full Text PDFRepeated use of field corn (Zea mays L.) hybrids expressing the Cry3Bb1 and mCry3A traits in Nebraska has selected for field-evolved resistance in some western corn rootworm (WCR; Diabrotica virgifera virgifera LeConte) populations. Therefore, this study was conducted to characterize spatial variation in local WCR susceptibility to Cry3Bb1 and mCry3A traits in Keith and Buffalo counties, Nebraska, and determine the relationship between past management practices and current WCR susceptibility.
View Article and Find Full Text PDFThe current International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) methods for determining the supported shelf life of a drug product, described in ICH guidance documents Q1A and Q1E, are evaluated in this paper. To support this evaluation, an industry data set is used which is comprised of 26 individual stability batches of a common drug product where most batches are measured over a 24 month storage period. Using randomly sampled sets of 3 or 6 batches from the industry data set, the current ICH methods are assessed from three perspectives.
View Article and Find Full Text PDFSound design of experiments combined with proper implementation of appropriate statistical methods for data analysis are critical for producing meaningful scientific results that are both replicable and reproducible. This communication addresses specific aspects of design and analysis of experiments relevant to the dairy sciences and, in so doing, responds to recent concerns raised in a letter to the editor of the Journal of Dairy Science regarding journal policy for research publications on pen-based animal studies. We further elaborate on points raised, rectify interpretation of important concepts, and show how aspects of statistical inference and elicitation of research conclusions are affected.
View Article and Find Full Text PDFImplicit in ICH Q1E (International Conference on Harmonization [ICH], 2003b ) are definitions of batch shelf life (the time the batch mean crosses the acceptance limit) and product shelf life (the minimum batch shelf life). The distribution of batch means over time projects to a distribution of batch shelf lives on the x-axis. Assuming multivariate normality, shelf life is the ratio of correlated Gaussian variables.
View Article and Find Full Text PDFThe goal of shelf life estimation is to determine the storage time during which the entire product meets specification with acceptably high probability. The estimated shelf life should be "applicable to all future batches" (ICH Q1E, International Conference on Harmonization, 2003b). There is compelling evidence of issues with the International Conference on Harmonization (ICH) guidelines for shelf life estimation.
View Article and Find Full Text PDFThis article proposes new terminology that distinguishes between different concepts involved in the discussion of the shelf life of pharmaceutical products. Such comprehensive and common language is currently lacking from various guidelines, which confuses implementation and impedes comparisons of different methodologies. The five new terms that are necessary for a coherent discussion of shelf life are: true shelf life, estimated shelf life, supported shelf life, maximum shelf life, and labeled shelf life.
View Article and Find Full Text PDFInt J Inf Technol Decis Mak
September 2009
Methods for identifying meaningful growth patterns of longitudinal trial data with both nonignorable intermittent and drop-out missingness are rare. In this study, a combined approach with statistical and data mining techniques is utilized to address the nonignorable missing data issue in growth pattern recognition. First, a parallel mixture model is proposed to model the nonignorable missing information from a real-world patient-oriented study and concurrently to estimate the growth trajectories of participants.
View Article and Find Full Text PDFAlthough several neurodevelopmental and psychiatric disorders can emerge during the preschool period, there are comparatively few instruments to assess executive control. Evidence for validity of the Shape School (K. A.
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