Cut point evaluation

Occasionally, naive samples are encountered with preexisting or high levels of ADAs. If a confirmatory test shows that the ADA response is specific to the drug, such samples should be excluded from the cut point calculations. In addition, samples that are identified as outliers using appropriate statistical criteria [34] should also be excluded or down weighted in the analyses. If a substantial number of naive samples are positive from the relevant disease population, it is acceptable to include samples from a healthy or non-diseased population for determining the cut point. For example, if the distribution of the data of outlier-removed samples is not statistically different between healthy and disease-matched subjects (i.e., means and variances are not significantly different), then the cut point evaluation can be made from a collection of samples where half the samples are from healthy subjects and the other half are from the relevant disease population. 

Appendix 8.A.4 Determination of Correction Factor for Screening Cut Point Evaluation... 

C-E Raymond s experience in the classification of powdered materials and the success of the JetStream classifier in providing consistently sharp cut-points at full production capacities can be put to work for you to help provide the kind of quality product you demand. For a no-cost evaluation of your application, simply remove this sheet, answer the questions below, fold and mail. If you need assistance, call us at (312] 236-4044. 

Hie objective of MAT testing in many labs is to compare both activity and selectivity differences between catalysts. Given that a variety of testing approaches are in practice, what effects do these methods have on ranking of catalysts To answer this question the three catalysts summarized in Table 1 were evaluated using seven different steaming/MAT approaches. Table 4 summarizes the seven methods evaluated. The definitions for cut points in this study are C5-421°F (gasoline), 421-602°F (LOO) and 602°F-plus (bottoms). Dry gas includes H2, H2S and C1-C2 hydrocarbons. LFG are the C3-C4... 

Since hsCRP values minimally correlate with Upid concentrations and lipid parameters account for <3% to 5% of the variance in hsCRP measurement, the measurement of hsCRP does not replace but instead complements the evaluation of lipids and other classical CHD risk factors in primary prevention settings. Data from the WHS demonstrated that hsCRP adds prognostic information not only at all levels of the risk defined by current LDL cut points of the NCEP but also at ah levels of the risk specified by the Framingham risk score algorithm. ... 

FIGURE 8.2 Scheme for evaluating cut point samples and calculating screening cut point. Source Figure courtesy of Ref. [34]. 

Dynamic Cut Point A cut point that is evaluated separately for each plate/run/ study and does not use the data from prestudy validation is defined as a dynamic cut point. A practically limiting factor is that a significant number of samples are needed in each plate/run to compute this cut point. When differences between runs (means and/or variances) are encountered, an investigation of the source of such differences is recommended. For example, if these differences were primarily due to analysts or instruments, then one should consider the appropriateness of analyst or instrument specific fixed or floating cut points before instituting a dynamic cut point approach. 

Titration Assay Using a dilution profile of an ADA-positive sample, titer is defined by the reciprocal of the dilution of the sample that corresponds to the screening assay cut point (interpolation method). Alternatively, instead of interpolation, it is sometimes defined by the reciprocal of the lowest dilution whose signal falls below the screening assay cut point. In these evaluations, it is important that the... 

Appendix 8.A.2 Evaluation of Cut Point Based on the Validation Data... 

Appendix 8.A.5 Evaluation of Screening Cut Point During the In-Study Phase... 

In addition, tabulated data from calibration curves, precision and accuracy data sets, selectivity experiments (spiking of matrices from individual sources), and baseline evaluations (for cut point analysis) will provide valuable information on method performance and should be compared with similar data sets from the sending lab. 

Bamonti, F., Moscato, G.A., Novembrino, C., Gregori, D., Novi, C., De Giuseppe, R., Galli, C., Uva, V., Lonati, S., and Maiavacca, R., 2010. Determination of serum holotranscobalamin concentrations with the AxSYM active B12 assay cut-off point evaluation in the clinical laboratory. Clinical Chemistry and Laboratory Medicine. 48 249-253. 

Different laboratories may use different methods for the evaluation of feedstock quality. Method variation makes it difficult to compare the data among laboratories. For example, when comparing the properties of different feedstocks - for instance their SARA analysis - the feedstocks should have been distilled to the same nominal cut point. The data in Table 5 show that... 

In this chapter we shall derive and present relationships or formulae that will allow us to predict a cyclone s cut-point diameter, grade-efficiency curve, overall or gross efficiency, and pressure drop on the basis of measurements taken on a geometrically similar cyclone. These formulae should also allow us to evaluate the performance of an operating cyclone and, if necessary, assist us in troubleshooting its design, mechanical condition, or mode of operation. 

The flash point measures the tendency of a petroleum material to form a flammable mixture with air. It is one of the properties to be considered when evaluating the flammability of a petroleum cut. 

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