Validation meaning

Productivity is a measure of productive efficiency calculated as the ratio of what is produced to what is required to produce it. Productivity can therefore be considered as a characteristic of a process, and therefore a measure of the quality of a process. Consider two process each producing the same product but one delivers the result using less resources and hence as a consequence has a higher productivity. The process with the higher productivity could thus be regarded as being of better quality. However, measuring resource consumption alone would not be a valid means of comparison as inputs could be vastly different. Hence productivity is a quality characteristic. 

Expressing the design output in terms that can be verified and validated means that the requirements for the product or service need to be defined and documented. The design input requirements should have been expressed in a way that would allow a number of possible solutions. The design output requirements should therefore be expressed as all the inherent features and characteristics of the design that reflect a product which will satisfy these requirements. Hence it should fulfill the stated or implied needs, i.e. be fit for purpose. 

The FDA mandates that of all the calibration concentrations included in the validation plan, the lowest jc for which CV < 15% is the LOD (extrapolation or interpolation is forbidden). This bureaucratic rule results in a waste of effort by making analysts run unnecessary repeat measurements at each of a series of concentrations in the vicinity of the expected LOD in order to not end up having to repeat the whole validation because the initial estimate was off by + or - 20% extrapolation followed by a confirmatory series of determinations would do. The consequences are particularly severe if validation means repeating calibration runs on several days in sequence, at a cost of, say, (6 concentrations) x (8 repeats) x (6 days) = 288 sample work-ups and determinations. 

Measuring pH in fundic juice aspired when entering the stomach during endoscopy is thus a simple, robust, and valid means of testing the gastric acid barrier, and pH >3 indicates failure. 

The degree of validation of the methods may be quite different. What validation means is that the method has been subject to a study which shows that, as applied in the user s laboratory, it provides results which are fit for their intended purpose. The method satisfies some pre-defined criteria. When standard or internationally agreed methods are being developed, the validation of the method is more complicated and time-consuming than that of methods developed in-house. Such validation involves a collaborative study using analysts working in a number of laboratories. This has already been mentioned in Chapter 1 and the organization of collaborative studies is discussed in Chapter 7. However, this more elaborate procedure does not necessarily mean that the method is more reliable than in-house methods. 

The computerized systems, both hardware and software, that form part of the GLP study should comply with the requirements of the principles of GLP. This relates to the development, validation, operation and maintenance of the system. Validation means that tests have been carried out to demonstrate that the system is fit for its intended purpose. Like any other validation, this will be the use of objective evidence to confirm that the pre-set requirements for the system have been met. There will be a number of different types of computer system, ranging from personal computers and programmable analytical instruments to a laboratory information management system (LIMS). The extent of validation depends on the impact the system has on product quality, safety and record integrity. A risk-based approach can be used to assess the extent of validation required, focusing effort on critical areas. A computerized analytical system in a QC laboratory requires full validation (equipment qualification) with clear boundaries set on its range of operation because this has a high... 

This test uses the entire HPTC system with a specific chromatographic method and validated Cl8 column that should be <10 cm and commercially available. Validated means that the individual column was performance tested before being shipped and that a certified test chromatogram is included with each column. Injection precision testing is typically performed by replicate injections of a test standard (at least six replicates are suggested). One then calculates the peak area %RSD of a stable component in the test standard. Most LC... 

Process validation means establishing documented evidence that provides a high degree of assurance that a specific process will consistently produce a product meeting its predetermined specifications and quality characteristics. 

Validation means doing what is necessary to demonstrate that a process is mastered and avoiding excessive formal exercises by setting priorities based upon risk assessment. 

In this connection, a difficult problem is how to validate such models to analyze their reliability. The absence of adequate validation means that the results of numerical modeling using integral models can be considered only as possible scenarios—but not forecasts. 

Incomplete process validation (meaning that critical process parameters are not adequately challenged)... 

The concept of validation came up in the 1970s in association with sterilization procedures and was extended to all steps of pharmaceutical manufacturing procedures. Validation means proving that any and all procedures, processes, equipment, material, operations, and systems comply with the expected performance. Well-planned and well-conducted validation studies constitute GMP principles once they guarantee a consistently safe and efficacious final product. Validation is important for companies, first for QA, and also for cost reduction, decreasing failures, rejection, reworks, recalls, and complaints. The positive aspect of validation is an increase in productivity, as a consequence of a well-controlled process. Validation is required by the regulatory agencies of many countries. 

Furthermore, the project team must validate the intent to establish a new business or integrate the project into an existing business. If the team plans to establish a new business, validation means proving that hiis will be the best way to commercialize the product and that support from a business would not positively... 

Although many researchers ackowledged that there was some inconsistency in using a larger basis set for the complex than for the monomers, there was initial reluctance to accept the counterpoise procedure as a valid means to correct the problem when it was first introduced. The chief source for this skepticism lay in the numerical results. Many of the early calculations of H-bonded complexes relied on fairly small and inflexible basis sets. It is now known that bases of this type tend toward potentials that are much less attractive than the true potential. Limitations of the era also prohibited application of correlation in most cases, eliminating a major attractive component. As a result, the H-bond attractions corresponding to these treatments are much too weak. It was only the superposition errors that were hidden in the calculations that permitted the final results to be even slightly attractive. In other words, if one does not analyze the results carefully, one can easily be misled since the spurious attractive nature of the BSSE can compensate in some sense for the unsatisfactory character of the calculations themselves. 

The results of this study support three basic conclusions (1) The CS system is a valid means for collecting surficial seafloor samples for pollution studies (2) the basic assumption of this study—that the fine-sediment fraction of marine sediments are the primary host of heavy metal contaminants injected into the marine waters—is correct and (3) the shipboard XRF system formerly designed as a qualitative means for assisting in selecting more precise sampling areas while at sea can now be considered as a valid analytical tool capable of producing quantitative data. 

Sometimes, the notion of validating a measurement result also shows up. Apparently it means to make a result valid , and even binding, i.e. confirming its validity . Since valid means seen to be in agreement with the facts , that almost sounds as a synonym for accurate . That makes sense and there seems to be no argument as to whether a method or a result can be validated (they can). An important question arises does a validated method automatically give a validated measurement result, i.e. a quantity value1 with asso-... 

Equation (15) is also valid, meaning that the process is under complete diffusion control at all overpotentials when jo -> oo if /L > 0 and Sw > 0. 

MichaeUs Constants. Roche (R19) and Sarles (S6) suggested that the measurement of the afiBnity constant of the substrate for alkaline phosphatase might be a valid means of characterizing the organ sources in hyperphosphatasemia. Later, Moss and King (M36) were able to characterize isoenzymes in different tissues by the determination of Michaelis constants with j3-naphthyl phosphate as substrate. The tissue difference in values, although small, was found to be reproducible. 

Validation means to prove that a developed system (product, program, protocol,. ..) meets some goals that have been specified a-priori. Thus, before models can be used to identify causes and effects [1009], it must be checked whether they are valid representations of the systems in consideration. To meet these requirements for the simulation model of the PA6 design process. 

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