Data collection/analysis quality control

An Improved disc centrifuge photosedimentometer (DCP) was developed for use in the determination of the particle size and size distribution of latices, pigments and other particulates. Separation is based on Stokes Law for the sedimentation of particles in a centrifugal force field and does not rely on the use of particle size calibrants or standards. The DCP Instrument provides accurate stable particle size analyses over a wide range of conditions while at the same time is rugged enough for heavy use in both a research and quality control environment. A stand-alone data collection, analysis and management system was developed both for routine quality control operation and for research use of the instrument. 

Statistics C CHATFIELD Data collection and analysis quality control reliability... 

Humidity J COMYN Relative humidity, laboratory control of humidity Statistics C CHAIEIELD Data collection and analysis quality control reliability... 

The principal tool for performance-based quality assessment is the control chart. In a control chart the results from the analysis of quality assessment samples are plotted in the order in which they are collected, providing a continuous record of the statistical state of the analytical system. Quality assessment data collected over time can be summarized by a mean value and a standard deviation. The fundamental assumption behind the use of a control chart is that quality assessment data will show only random variations around the mean value when the analytical system is in statistical control. When an analytical system moves out of statistical control, the quality assessment data is influenced by additional sources of error, increasing the standard deviation or changing the mean value. 

When sampling in the enviromnent, it is often impossible to determine which chemical mixtures are causing a total petroleum hydrocarbons reading, which is one of the major weaknesses of the method. At minimum, before using contaminants data from diverse somces, efforts should be made to determine that field collection methods, detection limits, and quality control techniques were acceptable and comparable. This will help the analysts compare the analysis in the concentration range with the benchmark or regulatory criteria concentrations should be very precise and accmate. 

Data have been collected since 1970 on the prevalence and levels of various chemicals in human adipose (fat) tissue. These data are stored on a mainframe computer and have undergone routine quality assurance/quality control checks using univariate statistical methods. Upon completion of the development of a new analysis file, multivariate statistical techniques are applied to the data. The purpose of this analysis is to determine the utility of pattern recognition techniques in assessing the quality of the data and its ability to assist in their interpretation. 

The two research investigations reported here - the sensory quality control specification model and the application of sensory and analytical data for defining differences in tobacco aroma - both demonstrate the usefulness of multivariate analysis techniques for analyzing analytical and sensory data as well as correlating these data. Although these tasks do not compare in complexity to that of the prediction of sensory response to analytical data collected on cigarette smoke, our research to date has revealed no element which indicates that this is an impossible task. In fact, the results of these and similar... 

The bioanalytical laboratory should have a written set of standard operating procedures (SOPs) to ensure a complete system of quality control and assurance. The SOPs should cover all aspects of analysis from the time the sample is collected and reaches the laboratory until the results of the analysis are reported. All deviations from SOPs must be authorized by the study director and documented in the raw data. Significant changes in established SOPs must be properly authorized in writing by management. 

The following discussion will focus on how to apply the previously discussed concepts to the validation of marketed products. To provide a fuller understanding of this procedure, the manufacture of several dosage forms designed for different routes of administration will be examined. For each dosage form, critical process steps and quality control tests will be identified. Useful statistical techniques for examining the assembled data will be illustrated. It is also important to note that not all of the collected information for a product lends itself to this type of analysis. This will become more apparent as we proceed with the evaluation of the five drugs under consideration. 

Quality control procedures are generally established to provide checks on the data that have been collected to evaluate whether in fact the quality assurance procedures were followed and whether the data meet agreed-upon norms. Otherwise, it is difficult for the user to judge the integrity of a data set per se, because there may be few ways to tell that procedures were not followed or values properly recorded. Quality control measures can be linked to the quality assurance procedures. In the example given above for use of field blanks, spikes and duplicate samples, laboratories must provide evidence that their analysis of these samples meets acceptable statistical guidelines for accuracy and precision. Quality control can also simply involve careful analysis of a data set to determine whether it is internally consistent. 

HTS accelerates the identification of drug leads through the analysis of enormous numbers of samples in a series of automated assays (primary assays) run repetitively by robots. To decide whether to accept or reject the assay results, scientists validate the assay, analyze the data collected, and monitor whether the assay runs according to protocol. Several quality control procedures have been developed to evaluate the screening results and to... 

In the lab, future expansion plans include the use of optical scanners for reading sample labels, operation of robots to relieve some of the manual operations and an artificial intelligence system to track quality control. In other areas, there will be an increase in the number of real time monitors, not necessarily because real time data is needed, but the cost can be small compared to sending out a field team. There will be some applications of direct monitoring by satellites such as LANDSAT D. Both of these will be incorporated into water quality models which will allow more intelligent choices of where to send a field team to collect samples for detailed analysis. 

Quadrupole filter mass spectrometer, 255 Quality assessment, external, 118, 123 Quality assurance, 118 Quality control, analysis of results, 123 choice of method, 126 data collection, 120 in clinical analysis, 118-127 in immunoassays, 156 internal, 118 serum pools, 119 Quantification, general notice, xvi in gas chromatography, 190 in high pressure liquid chromatography, 208 in mass spectrometry, 262 in thin-layer chromatography, 167 Quartamon, 379 Quarzan, 473... 

In this section a concise overview of the most widely used analytical procedures for the determination of PCBs in environmental matrices (namely, air, sea water, snow/firn/ice, sediment/soil and biota) is given. Regardless of the nature of the sample, the following steps are generally included in an analytical procedure i) sample collection and storage ii) sample preparation (extraction of the analytes and cleanup of the extract) iii) instrumental analysis iv) data evaluation, including analytical quality control. 

Today, a number of pharmaceutical companies dealing with HTS reach a turnover of more than 15 different assay systems a year, in which 300,000 samples or even more are tested. This confronts the scientist with more than 5,000,000 data points which point to the need for efficient automation at all stages of HTS, even in data collection, data quality control and analysis. Robots, especially large systems integrated with multiple peripheral devices, are prominent at present. 

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