Qualitative factors, method development

Qualitative factors are also frequently considered in a robustness test. " For CE methods, factors such as the batch or manufacturer of the capillary, reagent or solvent can be selected. When evaluating the influence of such qualitative factor, the analyst should be aware that the estimated effect is only valid or representative for the examined discrete levels and not for any other level of that factor, and certainly not for the whole population. For example, when examining two capillaries X and Y, the estimated effect only allows drawing conclusions about these two capillaries and not about other capillaries available on the market. Such approach allows evaluating whether capillary Y is an alternative for capillary X, used, for instance, to develop the method. 

The above is not a complete statement of the theory of matter of Aristotle, but will, it is hoped, give an idea of the elaborateness and complexity of the Aristotelian concept, and serve to illustrate how far removed was his method of developing the theory from the inductive methods of modern science. The concept of the four elements as qualitative factors in the constitution of other bodies, with their inherent forces of heat, cold, moist, dry, became accepted by later centuries as basic truth. His notion of a fifth element, variously interpreted, also held a place in the thought of later times, but his more complex notions of the nature of the elements and matter had little influence on the later development of natural philosophy. 

We can easily quantify measurement error due to existence of a well-developed approach to analytical methods and laboratory QC protocols. Statistically expressed accuracy and precision of an analytical method are the primary indicators of measurement error. However, no matter how accurate and precise the analysis may be, qualitative factors, such as errors in data interpretation, sample management, and analytical methodology, will increase the overall analytical error or even render results unusable. These qualitative laboratory errors that are usually made due to negligence or lack of information may arise from any of the following actions ... 

Table 17-4 summarizes the qualitative influence of changing the gradient parameters on resolution, retention factor, and run time. The bold rows of Table 17-4 offer the best approach to reducing analysis time and will be discussed in more detail. The nonbold rows represent parameters that should be optimized during the initial stages of method development to optimize resolution. 

Counting polymorphs and solvatomorphs, delavirdine mesylate has been found in 12 different crystal forms, therefore presenting considerable difficulty in the determination of phase composition.63 Only through the combination of factor analysis with the quantitative IR technique could one develop a method useable in the characterization of research and production lots. The composition of drug lots consisting of mixtures of forms was identified through qualitative factor analysis, and quantitated using principal component analysis. Calibration models were developed for the determination of Form-VIII or Form-XH in Form-XI, and a standard error of prediction of 2.0% of either form was reported, with detection limits of 3-5%. 

In Reference 27, the responses from the 12-experiment PB design (Table 2.8) applied during the screening phase of a CE method development were all qualitative, that is, the selectivity factor S, the resolution Rs, and the analysis time t (Table 2.17). 

The analytic hierarchy process (AHP), developed by Saaty (1980), is a multicriteria decision making method for ranking alternatives. Using AHP, the DM can assess not only quantitative but also various qualitative factors, such as financial stability, feeling of trust, etc. in the supplier selection process. The buyer establishes a set of evaluation criteria and AHP uses these criteria to rank the different suppliers. AHP can enable the DM to represent the interaction of multiple factors in complex and unstructured situations. AHP does not require the scaling of criteria values. 

Thus it would appear that a moderate reduction of the maternal food intake does not materially influence the fetus. However, recent studies in man based on a better knowledge of nutritional requirements and evaluated by statistical methods have shed new light on the influence of maternal diet on fetal development. They have shomi that quantitative and qualitative factors of the maternal diet affect the condition of the infant at birth without causing inanition of the mother. These studies will be discussed later in a special section (p. 91). 

We will explore the two major families of chemometric quantitative calibration techniques that are most commonly employed the Multiple Linear Regression (MLR) techniques, and the Factor-Based Techniques. Within each family, we will review the various methods commonly employed, learn how to develop and test calibrations, and how to use the calibrations to estimate, or predict, the properties of unknown samples. We will consider the advantages and limitations of each method as well as some of the tricks and pitfalls associated with their use. While our emphasis will be on quantitative analysis, we will also touch on how these techniques are used for qualitative analysis, classification, and discriminative analysis. 

The information on the container and the development pharmaceutics is to cover the qualitative composition (polymeric and other), closure type and method of operation, tightness of the closure, dosing device information, tamper evidence and child resistance, stability of the product in the container, the method of administration of the medicinal product, any sterilization procedures, the ability of the container to protect the contents from external factors,... 

Where the specific impnrity is unavailable or is too costly, the use of composite or degraded samples is possible. This approach involves the nse of a dirty sample of a drug substance or the creation of a mixture of impurities through the in situ forced degradation method. Both of these approaches are best nsed for qualitative uses. In each of these mixtures, the impurities are present in unknown quantities. The real benefit of this type of impnrity standard is the low cost and the ability to unequivocally identify the peak loci of the impurities. When these mixtures are used in conjunction with a compendial standard and a well-developed set of relative response factors the resnlts will meet most analytical needs. 

Methods for Determining Biomarkers of Exposure and Effect. As noted in Section 6.1, methods are available for the qualitative and quantitative measurement of 2-hexanone after it is separated from its sample matrix (Anderson and Harland 1980 Fedtke and Bolt 1986 Nomeir and Abdou-Donia 1985 White et al. 1979). High-resolution gas chromatography for 2-hexanone analysis has been developed to the point that the instrumental capability to separate volatile analytes by HRGC is, for the most part, no longer the limiting factor in their analysis. Flame ionization detection has enabled detection at very low levels and MS has assured specificity in measurement. 

In the case of soils, there has been surprisingly little consideration of factors that modulate the bioavailability of metals. In this respect it is necessary to develop methods that contain qualitative and quantitative descriptions of differences in bioavailability between soils typically used for laboratory testing and field soils, between contaminated and noncontaminated (natural background) soils, and among contaminated held soils. 

KJ Method was named after Jiro Kawakita, a man of many talents who was a professor of cultural anthropology in Japan. After extensive field research in Nepal during the 1960s, Kawakita developed the KJ Method to improve the integration and categorization of qualitative data around such factors as the environment, population, relationships, hierarchy, and religion. 

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