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Quality Management Tools - Data Quality Assessment
Data Quality Assessment is used to assess the type, quantity, and quality of data in order to verify that the planning objectives, Quality Assurance Project Plan components, and sample collection procedures were satisfied and that the data are suitable for its intended purpose. Data Quality Assessment is a five-step procedure for determining statistically whether or not a data set is suitable for its intended purpose. This assessment is a scientific and statistical evaluation of data to determine if it is of the type, quantity, and quality needed and may be performed either during a project to check the process of data collection or at the end of a project to check if objectives were met.
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References
- Data Quality Assessment: A Reviewer’s Guide (QA/G-9R) (PDF 61pp, 225K) provides general guidance to organizations on assessing data quality criteria and performance specifications for decision making. G-9R is non-technical document and shows a reviewer what constitutes an appropriate Data Quality Assessment (DQA), and how to recognize situations or reports where a DQA has been conducted.
- Data Quality Assessment: Statistical
Tools for Practitioners (QA/G-9S)
(PDF 198pp, 1.5MB). This document can be considered the technical aspect
of G-9R. The document is designed as a "tool-box" of useful
techniques in assessing the quality of data. The overall structure of
the document will enable the analyst to investigate many different problems
using a systematic methodology.
- Checklist for Quality Concerns
(PDF 6pp, 148K) - Draft checklist and list of resources for evaluating
secondary data.
- EPA's Science Policy
Council Assessment Factors - General Assessment Factors for Evaluating
the Quality of Scientific and Technical Information
Training
- Introduction to Data Quality Assessment
- This one-day course demonstrates how to perform a data quality assessment
to evaluate data and provides detailed information on graphical and
statistical tools. This course will familiarize participants with the
process for performing a data quality assessments. It does not involve
detailed instructions on the statistics involved in the process.
- Interpreting Monitoring Data
- This half day course teaches participants how to deal with monitoring
data using statistics. At the end of the course the participants
will understand the need to incorporate systematic planning into
monitoring activities, realize the importance of representativeness,
be able to graphically view the data, and gain an insight into the
complexities of statistical analyses of monitoring data.
- Interpreting Multivariate Analysis
- This half day course covers multivariate analysis techniques to explore
relationships among several variables in an effort to understanding
an environmental problem. A prerequisite of the course is a general
understanding of data collection and elementary statistical analysis.
Examples and Other On-line Resources
- Software - For links to free software for performing data quality assessment, see Quality-Related Resources - Software. EPA has a site license for SAS for EPA employees - information on the EPA Intranet at the EPA SAS Support Home Page.