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Resources for Planning Projects that Use Existing Data

Below are some links to help you get started.

Data Quality Assessment - Before existing data can be used, it will need to be assessed against its intended use.
Chapter 3 of the Guidance for Quality Assurance Project Plans (G-5) identifies elements to consider when planning projects that use existing data.
Checklist for Quality Concerns - 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
Software - For links to free software for performing data quality assessment, see Quality-Related Resources - Software.

Resources for Planning Projects that Use Existing Data

Managing the Quality of Environmental Information