Overview:

The chart audit validation process is performed to ensure the information collected is accurate.  To do this, CMS will take the following approach:

For each calendar quarter, all hospitals submitting abstracted data will be identified.
For each hospital, all abstracted charts will be enumerated.
A simple random sample of five charts will be identified from all hospitals with a minimum of six discharges in the QIO clinical Warehouse. 

The sample is selected from all the cases submitted and is not topic-specific.
The CMS Clinical Data Abstraction Centers (CDAC) will request the paper medical records for each of the sample charts.
The CDAC will re-abstract the chart using the CMS Abstraction & Reporting Tool (CART). 
The relevant differences will be identified and the CDAC will assign a reason code to each difference noted.
The results of the re-abstraction will be stored in the QIO Clinical Warehouse and made available to the QIO to provide feedback to each hospital.
Hospitals will receive educational feedback including an overall reliability rate and case details on each abstraction.
Based upon the CDAC re-abstraction, the percent agreement at the element level will be calculated.  Hospitals that reach or exceed the 80 percent pre-determined threshold will be considered to be supplying valid data for that quarter.
Measures for which there are found to be significant errors may not be posted on the website.