Method capability assessment

As shown in Figure 11, before extensive validation, the performance of the method is evaluated appropriately. Column durability tests, robustness testing for the chromatographic and sample preparation conditions, analytical method evaluation ring tests (AMERTs), method capability assessments, and pre-validation studies are applied to... 

The following considerations, when applied during method development, are likely to produce more robust, reliable, and transferable methods (a) the concerns of the customer (user) are considered in advance, (b) key process input variables are identified, (c) criticaTto-quality factors are determined, (d) several method verification tests are installed, (e) proactive evaluation of method performance during development is performed, (f) continuous customer involvement and focus are institutionalized, and (g) method capability assessment (suitability to be applied for release testing against specification limits) is established. 

B. Method Capability Assessment METHOD VALIDATION PHASE METHOD TRANSFER PHASE... 

A computer program is provided for ease of calculation and efficient use of the standard. This rational method of assessing hot environments allows identification of the relative importance of different components of the thermal environment, and hence can be used in environmental design. The WBGT index is an empirical index, and it cannot be used to analyze the influence of the individual parameters. The required sweat rate (SW. ) has this capability, but lack of data may make it difficult to estimate the benefits of protective clothing. 

Absorption and clearance are two of the fundamental parameters that determine oral bioavailability. There are many in vitro methods to assess the absorption and metabolic potential of a given molecule, and it can be argued that a combination of these data should produce a model capable of predicting oral bioavailability. Such a model, based on a graphical approach has recently been published [26]. 

A major objective in developing these risk estimation procedures was to provide a method capable of evaluating hundreds of properties in several communities within the DOE Uranium Mill Tailings Remedial Action Program in a timely manner. Therefore, we chose a calculation scheme that could be performed using commercially available database software (dBASE II, a trademark of Ashton-Tate, Culver City, CA), but that at the same time would be flexible enough that assessments for other contaminants could be readily incorporated. 

By applying a Gage R8cR study it is possible to assess the reproducibility and the method capability for process improvement/control and for acceptance testing against specifications. The following metrics are calculated ... 

Step 3 Feasibility assessment Detemiine (via literature search, consultation, etc.) suitable candidate methods and assess the feasibility of these methods. The purpose of this step is to collect enough information to accurately define (or scope ) and prioritize the project. The amount of information required may vary considerably, depending on the magnitude of the proposed project. Significantly less information is required to develop a new method for an existing off-line analyzer than is required to justify spending several million dollars on a major installation of on-line analyzers. (The capabilities and limitations of NIR process analyzers are discussed in Section 15.2.4.)... 

In order to prevent indiscriminate use, regulations have been developed by many countries limiting the types, uses, and amounts of food colors permitted in foods (142,151). Since different countries allow the use of specific food colors, it is possible that foodstuffs may be imported into a country that forbids the coloring agent present in the product. Therefore, methods capable of identifying and quantifying several colors simultaneously are desired in order to verify compliance to regulations. Information on the levels of these compounds in foods is also important to assess where the dietary intake levels stand compared to the ADIs (131,152,153). 

Psychomotor vigilance task performance has also been shown to be sensitive to reduced behavioral alertness associated with obstructive sleep apnea syndrome (OSAS), and the efficacy of interventions for OSAS. Performance of patients with OSAS is impaired on tasks that rely on the ability to sustain attention (85,86). As a measure of behavioral alertness, PVT performance has been demonstrated to be a sensitive method for assessing the attentional capability of patients with OSAS (32,87,88). Kribbs and colleagues (89) found that PVT performance and sleepiness, measured by the MSLT, both reflected the benefits of CPAP use (reduction in respiratory events during sleep). Similarly, the PVT has been used to demonstrate the positive effects of modafinil (a wake-promoting compound) on the capacity to sustain attention in a group of OSAS patients (34). 

Apply biological methods capable of accurate assessment of ecological effects that integrate mixture and bioavailability effects. 

The MT T assay is another colorimetric method to assess cell viability. NAD(P)H (nicotinamide adenine dinucleotide(P)H)-dependent cellular oxidoreductase enzymes may, under defined conditions, reflect the number of viable cells present. These enzymes are capable of reducing the tetrazolium dye MTT 3-(4,5-diwiethylfhiazol-2-yl)-2,5-diphenylletrazolium bromide to its insoluble purple-coloured formazan (Figure 7.71). In living cells, the originally yellow MTT is converted by cellular reductase to purple formazan (Mosmann, 1983). A solubilisation solution (usually either dimethyl sulfoxide or sodium dodecyl sulfate dissolved in diluted hydrochloric acid) is added to dissolve the insoluble... 

It did not start out that way. Over 25 years ago, Cleveland and McGill s experiments described human graphical perception capabilities and their application to the development of graphical methods by assessing individuals abilities to perceive various shapes and lines (Figure 11.1). 

National and transnational regulatory frames, improved awareness of health- and quality-related issues, and growing occurrence among the general population of adverse reactions toward some food components have increased the need for specific and sensitive methods capable of assessing specific food constituents, as well as additives, adulterants, and contaminants. 

---