Detectivity accuracy

Consideration must be given to equipment calibration and method suitability in terms of sensitivity, limits of detection, accuracy, precision, repeatability. 

The FSA undertakes surveillance exercises, the data for which are acquired from analytical determinations. The Agency will take measures to ensure that the analytical data produced by contractors are sufficient with respect to analytical quality, i.e. that the results obtained meet predetermined analytical quality requirements such as fitness-for-purpose, accuracy and reliability. Thus when inviting tenders FSA will ask potential contractors to provide information regarding the performance requirements of the methods to be used in the exercise, e.g. limit of detection, accuracy, precision etc., and the quality assurance measures used in their laboratories. When presenting tenders, laboratories should confirm how they comply with these specifications and give the principles of the methods to be used. These requirements extend both to the laboratory as a whole and to the specific analytical determinations being required in the surveillance exercise. The requirements are described in three parts, namely ... 

Mass spectrometry is often referred to as the gold standard for molecular detection and identification. Traditionally a lab-based research tool, MS is now being developed for automated operation in rugged environments by technically unskilled operators. It is therefore inevitable that MS will find a major role in security applications, particularly where detection accuracy outweighs the requirements for size and cost. In this chapter we compared IMS to MS, but in fact the determining factor regarding which detector to deploy depends on application. When inexpensive, handheld analyzers are required, IMS is the best choice. For stationary applications where compactness is less important then the superior performance of MS offers compelling benefits. 

Field measurement instruments should be checked for their limits of detection, accuracy, and reproducibility, and their measurement errors should be established. This can be done with standards, duplicate samples, and dilution of samples, similar to the checks discussed for laboratory measurements (section 5.9). Such checks should be performed in preparation for field work, and the results should be recorded and reported with the... 

When considering toxicity manifestation time and vapor dispersion, the detection sensitivity for vapor concentration is one hundredth of LCtso within 1 min. In the case of GB, this required detection sensitivity is 0.15 mg/m, and at this level there is no odor and humans show no signs of toxicity. In the chemical weapon disposal situation, because the workers stay in one place for a long time, the time weighted average (TWA) values are the monitoring target for allowed operational conditions. These TWA values are approximately 1/100,000 of LCtso. The desired alarm time is to be less than several minutes. There is a trade-off relationship between LOD, alarm time, detection accuracy and... 

First responders require the following criteria detection sensitivity, detection accuracy, response time, recovery time and operation Table 53.9 compares these items. The numerical data are derived from our experiment. The evaluation is categorized into the three signs OK means acceptable, A means improvement required, and X means not acceptable. There are no devices that meet all CBWA detection requirements. Low sensitivity, false alarms, and the strong adsorption of CWAs on certain... 

A single method of analyzing the hydrocarbon components of gasoline in tissue samples was located (Shankles et al. 1982). This method utilized HRGC/FID and involved injection of headspace gas. The limit of detection, accuracy, and precision of this method were not reported. 

The FSIS Test Review System was developed to encourage the development of new tests by making the testing requirements known to test developers, and by expediting and standardizing the review process. All methods designed to measure the same analyte will be evaluated by the same standard, e.g., HPIC methods, microbiological inhibition tests, and immunoassays for the same analyte would all be evaluated from the perspective of limit of detection, accuracy, and precision. 

The ability to focus molecular expression analysis on only a limited number of cell types depends on cell separation methods that minimize the opportunity for other cell types to contribute to gene expression in situ. Even the most carefully gathered biological samples contain many cell types, especially if the sample is from inflamed or necrotic tissue. More homogeneous samples are provided by laser capture microdissection (LCM), a method that isolates individual cells or sections of tissue from a fixed sample [144-148]. The use of LCM minimizes contributions by nontarget cell populations in comparisons of diseased and normal tissues, but also introduces handling and preparation steps that can affect detection accuracy. 

Tang, Y., Tao, Z., Bukowski, R.M., Tehan, E.C., Karri, S., Titus, A.H., Bright, F.V. Tailored xerogel-based sensor arrays and artificial neural networks yield improved 02 detection accuracy and precision Analyst, 2006, 131, 1129-1136... 

Sample Matrix Sample Preparation Analytical Method Detection Accuracy Limit Reference... 

Various studies performed over the years clearly indicate that the detection accuracy improves dramatically when a person moves a thin cloth or a piece of paper over the item/object surface instead of just using bare fingers [28]. 

CAD is attractive because it has the potential to overcome this difficulty that is, CAD has the potential to improve detection performance and reduce variability of detection accuracy among readers. 

The following analytical performance parameters were included into the validation process selectivity stability during chromatograidiic development and in solution spot stability prior to the run and after development linearity and range precision reproducibility limit of quantitation limit of detection accuracy. The definitions used for the performance parameters the methods applied to determine them and the acceptance criteria were also described. Therefore, these papers can be recommended to be used by practicising chromatographers. 

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