Data at Rest


Data at Rest (DAR) is the measurement of data residing in the immunization information system (IIS) database regardless of how it arrived there. This content area puts into practice data quality indicators found in the IIS Data Quality Practices – To Monitor and Evaluate Data at Rest (May 2018).

The Measurement and Improvement (M&I) Initiative measures DAR within two different stages using the following indicators:

  Testing & Discovery


Completeness 24 24
Validity  23 20
Timeliness 8 1


The concepts measured are defined as:

Completeness: The degree to which full information about a data set, record, or individual data element is captured in the IIS (i.e., the proportion of stored data with complete information measured against the potential of “100%”).

Validity: The degree to which the data conform to the syntax (format, type, range) of their definitions (i.e., to the rules of what is accepted or expected by the IIS).

Timeliness: The amount of time between the occurrence of the real-world event and its documentation in the IIS (i.e., the time lag between the date of vaccination or birth and the date the record is fully processed and ready to use in the IIS).

More information on the indicators and concepts can be found in Measures and Tests for Assessment: Data at Rest.

Participation in DAR

The measurement process and IIS level of involvement for the DAR content area differs from other M&I content areas in three key ways: uses de-identified production data instead of a connection to a preproduction environment, requires more direct engagement with IIS staff, and may require a partner agreement between AIRA and the IIS program. As with all other content areas in M&I, participation is voluntary but strongly encouraged for all IIS. 

Below are the steps and resources for participating in DAR, which are also outlined in the Data at Rest Participation Checklist

Step One: Project Initiation

Step Two: Data Extraction

Step Three: Data Transformation

Step Four: Data Loading

  • DAR Loading Guide – A guide on loading the Aggregate Detection File (ADF) into the Aggregate Analysis Reporting Tool (AART).
    • Note: An IIS jurisdiction can be measured with the same ADF file for both stages of measurement (Testing & Discovery and Assessment). Only one file is needed to participate. 

Step Five: Data Analysis

  • DAR Reports Guide - A guide on reviewing your DAR results and conducting analysis on the NIST tool qDAR (coming soon!).

Step Six: Data Quality Improvement

  • AIRA staff are available to meet with you to discuss your reports and help with next steps. Submit your request via AIRA’s online form.

Additional Resources

Updated: 12/29/23