Data Quality Assessment Report

Data Quality Assessment Report (DQAR) preparation... 

Data Quality Assessment Report (DQAR) is the last stone placed at the top of the data collection pyramid. The DQAR summarizes the data collection activities and states whether the data are of the right type, quantity, and quality to support their intended use. 

DOD DOT DQA DQAR DQIs DQOs DRO Department of Defense Department of Transportation Data Quality Assessment Data Quality Assessment Report Data Quality Indicators Data Quality Objectives diesel range organics... 

USEPA (1996b). Guidance for Data Quality Assessment Practical Methods for Data Analysis, Report No.600/R-96/084, United States Environmental Protection Agency, Washington, DC, USA. 

External quality assessment schemes involve the distribution by the organizer, to participating laboratories, of aliquots from the same sample. Participants analyze the received specimen and send the results back to the organizer who prepares a report to summarize all data. 

Measurements of individual laboratory performance provides for comparisons between laboratories. It then follows to ask why some laboratories report data that are more accurate and precise than do their peers, and a well designed external quality assessment scheme allows investigation of some of the important factors (see below). A comparison of performance between individual laboratories also helps to stimulate those who are not so successful to improve (or abandon the assay) and those who do well to continue with their expertise. Finally, changes of performance may be monitored as a consequence of some new factor, e.g. purchase of a new piece of equipment, work carried out by a different analyst, change to the methodology etc. 

W.W. Lapham, F.D. Wilde, and M. T. Koterba, Ground-Water Data-Collection Protocols and Procedures for the National Water-Quality Assessment Program Selection, Installation, and Documentation of Wells and Collection of Related Data, Open-File Report 95-398, US Geological Survey, Reston, VA (1995). 

The current distribution of geochemical data available through the national repository (OZCHEM database) is shown in Figure 1. The map shows that there are vast areas of the country (>60%) that lack any geochemical information. Also, where geochemical data are available, they are often not comparable as a result of incompatible sampling media, inconsistent sample preparation and analysis methods, incomplete quality assessment metadata and/or different analyte suites being reported. 

The assessment of project activities may include performance and systems audits, data quality audits, peer review, PE samples, as appropriate for a given project. Assessment enables project personnel to identify field and laboratory problems or variances from the project scope and to implement timely corrective action. The findings and response actions originating from assessment activities are documented in reports to management. 

A host of laboratory QC checks are encoded into data qualifier conventions designed to indicate specific QC deficiencies. Different laboratories may have different letters for identifying the same non-compliant events. The meaning of the data qualifier must be explicitly annotated in the reported data. During data evaluation in the assessment phase of the data collection process, the data user will determine the effect of these deficiencies on data quality and usability. 

Part 2 of this Harmonization Project Document is on data quality for chemical exposure assessment, because of its importance to the acceptance and credibility of the evaluation of uncertainty in an exposure analysis. Data quality for the purposes of this report deals with the completeness and clarity with which uncertainty is explained. This means that data with high uncertainty may be of high quality if the data and its uncertainty are clearly explained and carefully documented. A high-quality evaluation of uncertainty in an exposure analysis would provide the readers with the ability to re-evaluate all the choices and trade-offs made in the evaluation and to explore alternative choices and trade-offs. This is a difficult goal to achieve in most cases. 

Hallmarks of data quality are important to the characterization and communication of uncertainty, not just from the perspective of the exposure analyst, but also from the perspective of the target audiences for the exposure assessment. For example, lack of transparency in a source document (e.g. a monitoring study) used in the assessment should be considered by the original investigators as a source of uncertainty, whereas lack of transparency in the report of the exposure assessment may introduce uncertainty or lack of confidence from the perspective of its likely users. 

The reports provided to participants in external quality assessment schemes should contain a munb of important values. As illustrated in Fig. 5, most schemes include data such as the number of participants accepted in the final analysis, the mmiber rejected, i.e. the outliers, the mean and standard deviation of the accepted results, the spiked value together with the individual participant s value and its standard deviation interval (si) from the consensus mean. In addition, a computerised frequency distribution histogram is generally provided. 

Koterba, M. T, WUde, F. D., and Lapham, W. W., 1995, Ground -water data-collection protocols and procedures for the National Water-Quality Assessment Program Collection and documentation of water quality samples and related data U.S. Geological Survey Open-File Report 95-399, 113 p. 

The large numbers of compounds synthesized by HTOS and purified by HTP require high throughput analysis and quality assessment. Mass spectrometry is commonly used for this purpose. Research and development in the analysis of libraries have been focused primarily on the improvement of throughput and automation in the analysis, interpretation, and reporting of data. Morand et al. have recently reviewed development of high throughput mass spectrometry in pharmaceutical research [20] for the analysis of chemical library compounds. Also, the use of one or more auxiliary detection techniques, such as UV or ELSD in addition to mass spectrometry, allows for better assessment of the purity of library compounds. 

At the national level, the General Monitoring Network of air quality (GMN), established in 1985, is the largest one. It is subordinated to the SSI and operated by its provincial (or local) branches. Its main purpose is to supply information on population exposure to air pollutants for the needs of the National Health Programme. Data are also used for environmental policy purposes. Stations belonging to the network are also a part of lower level monitoring systems - the collected data are used both at the local and voivodship level. In 1997 the network consisted of 506 stations, located in cities above 20 thousand inhabitants and in health resorts. The basic monitored pollutants are SO2, NO2, black smoke and TSP. In total, 37 pollutants (from 1 to 19 compounds at each station) were monitored in 1997. Almost exclusively manual 24-hr measurements are carried out at the stations. The network is supervised by the Nofer Institute of Occupational Medicine (since 1992 till 1999), which is responsible for QA/QC, data collection, assessment and reporting. 

Figure 3 Illustrates the problem faced by the IAEA in the broader context of their trace element laboratory intercomparison program. These data show the reported results of 16 laboratories for measurements of arsenic in the horse kidney intercomparison sample (H-8), based on various versions of atomic absorption spectrometry, optical emission spectrometry, neutron activation analysis, and Induced X-ray emission analysis. The objective of the horse kidney intercomparison was to assess (and refine) analytical methods for the determination of essential and toxic trace elements in this surrogate for human kidney (2). Kidney, as the main target organ which accumulates toxic elements, was of special Interest with respect to cadmium. Horse kidney, which contains similar levels of cadmium to the human kidney cortex, was selected for the development and maintenance of methods having a demonstrated level of quality to assure reliable biological monitoring of this element. Participants were Invited to analyze some 24 additional trace elements, however.

Financial ratios are condensed data reporting quantifiable facts. With their help, complicated facts, structures, and procedures of corporations are depicted in a simple way to permit a fast and comprehensive overview. Thus, financial ratios are appropriate for the complex task of comparative credit quality assessment. To simplify the methodology, the number of financial ratios used should not be too large, and every financial ratio must be economically plausible. The selection of particularly appropriate financial ratios is a significant component of every rating methodology. These financial ratios should represent areas of relevance for creditors as exactly as possible, like debt/equity ratio, profitability, and liquidity. In this context, not only the level of these financial ratios is important but also their development over time. 

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