Screen confirmation

In the second study the same group evaluated the effects of prenatal cocaine exposure on child behavior in 506 African-American mother-child pairs (363). The mothers were identified as cocaine users and non-users during the initial prenatal visits with urine screen confirmation. Offspring behavior was assessed 6-7 years later using caregiver reports with the Achenbach Child Behavior Checklist (CBCL). Analyses stratified by sex and prenatal alcohol exposure showed that behaviors in girls without prenatal alcohol exposure but with prenatal cocaine exposure were adverse 6.5% of the unique variance in behavior was related to prenatal cocaine... 

Hughes, J.M. et al., A comparison of LC/MS mass analyzers for screening, confirmation and quantification of drugs in blood, Proceeding of 56th ASMS Conference on Mass Spectrometry and Allied Topics. Denver, CO, June 1-5, 2008. 

Unlike fully quantitative methods that utilize the reference standard curve to estimate the analyte levels in the study samples, sensitivity of ADA assays perse is not a critical validation characteristic. This is because, for the reasons described in Section 8.2, the screening, confirmation, and characterization of ADA-positive samples are based on the assay response unit rather than the ADA concentration levels. In addition,... 

The decision on which type of method to use for the ADA screening/confirmation assays will depend upon the structure of the drug and conclusions from the risk assessment. The most common and first approach is to use an ELISA-based LBA method, which offers quick development times, high throughput, and low cost. However, more complex method platforms (possibly more sensitive) such as, ECL or SPR assays may need to be developed if the ELISA platform does not meet the program s needs. While not commonly used, RIPA methods can provide many of the positive attributes of the ELISA with increased sensitivity. 

Data sheet from BIO-RAD on Urin Toxicology Screen Confirm Control Lyphocheck , Bio-Rad Laboratories GmbH, Mtinchen, 10/93. 

Fig. 32.5. Changes in the usage of the total screening capacity from primary HTS to in-depth hit characterization. HTS high throughput screening. Confirmation repetition of assay for hits with duplicates. Validation IC50 determination. Control tests tests for interference with the assay system. Profiling tests to characterize the properties of the inhibitors. 2006 data predicted.

Figure 1 outlines a typical approach to chemical safety evaluation. The approach uses screening, confirmation, and risk-estimation phases. It is designed to maximize compound flow-through with minimum time and expense. Again, specific tests included in each level must be selected according to the nature of the compound under investigation. 

Keywords dioxin PCDD PCDF dioxin-like PCB TEF TEQ WHO screening confirmation HRGC/HRMS accurate mass MID... 

Low JJ, Benin Al, Jakubczak P, Abrahamian JF, Faheem SA, Willis RR. Virtual high throughput screening confirmed experimentally porous coordination polymer hydration. J Am Chem Soc 2009 131 15834-42. 

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