Evidence Documents

Evidence Documents (ED) specifies how data objects such as digital measurements are created, exchanged, and used.

Summary

The Evidence Documents Profile allows data such as OB measurements, CAD results, procedure logs, etc. to be encoded, stored and managed just like DICOM images.

• The modality can store them to PACS.
• A reporting station can query and retrieve them along with the images.

Because they are structured and coded data, the receiving system can reliably parse the data and do things like:

• Compare measurements against normal ranges
• Insert measurement values into the correct part of a diagnostic report
• Calculate the different from the previous measurement on the same patient
• Plot measurements taken from several different studies on a curve

<GRAPHIC: Thinking of some Evidence Document icon in the middle. Coming into it from the left, Echo measurements, Chest CAD, Procedure Log. Going out to the right, Report/Reading Workstation, Clinical trend graph, Orthopedic Planning station maybe>

Benefits

• Avoids potential errors from parsing raw text (ambiguous measurement name, unclear units, etc.)
• Digital measurements from modalities stay digital
  • Faster, automated, reliable
  • Avoids errors from mis-reading or mis-dictating screen printed paper copies
  • Avoids errors from mis-heard or mis-typed dictations
  • Avoids need for radiologist to retrieve the measurement form and compare the numbers when verifying the transcribed report
• Opens the door to additional decision support, clinical pathways and other automation

Details

These non-image data objects may be produced by a number of different systems.

A Modality that performs measurements during a study, for example an ultrasound system with a cardiac package for measuring cardiac dimensions and calculating values like ejection fractions might create an Evidence Document containing those values and send it to the archive together with the study images.

A CAD workstation performing, post-processing on a Chest study might create an Evidence Document containing the results of the CAD analysis and add it to the archive.

Evidence Documents are based on DICOM Structured Reports (SR) which is sort of like XML for DICOM. Most Evidence Documents will be based on SR Templates defined by DICOM for particular purposes. For example, DICOM has templates for:

• OB/GYN Reports
• Mammography CAD Results
• Echocardiography Procedure Reports
• Cardiac Stress Testing Results

Other templates exist and more are being added each year. In the absence of a relevant template, a system can follow one of the general purpose templates.

Systems Affected

• Imaging Acquisition Modalities might create, retrieve and/or process Evidence Documents
• Clinical Workstations might also create, retrieve and/or process them
• CAD Systems may create them
• PACS may store and manage them
• Display systems may query, retrieve and display them
• Reporting workstations may retrieve, process and include details from them in reports

Actors & Transactions:

Specification

Profile Status: Final Text

Documents:

• IHE Radiology Technical Framework

Underlying Standards:

• DICOM

See Also

Related Profiles

• Scheduled Workflow [SWF] and/or Post-Processing Workflow [PPWF] manage the production of Evidence Documents. One of these profiles must be implemented together with the Evidence Documents Profile.

• Patient Information Reconciliation [PIR] is expected to reconcile Evidence Documents along with the rest of the patient data record.

• Reporting Workflow [RWF] may use Evidence Documents as inputs to the reporting process.

• Simple Image and Numeric Report [SINR] may include data copied from Evidence Documents.

• Cross-enterprise Document Sharing for Imaging [XDS-I] can be used to share Evidence Documents between sites over a network.

• Portable Data for Imaging [PDI] can store Evidence Documents on media such as CDs.

• Import Reconciliation Workflow [IRWF] can fix patient ids, etc. of Evidence Documents when importing.

Consumer Information

The Evidence Documents FAQ answers typical questions about what the Profile does.

Evidence Documents Purchasing describes considerations when purchasing equipment to deploy this Profile.

Implementer Information

Evidence Documents Implementation provides additional information about implementing this Profile in software.

Reference Articles

<List References (good and bad) (with link if possible) to Journal Articles that mention IHE's work (and hopefully include some analysis) >

This page is based on the Profile Template