DIR Training Webinar Series FAQ: All About Mapping

The Dose Index Registry (DIR) Training Series aims to inform facilities about how to get the most value out of participation and strategies to improve your facility's processes for better patient care. Accurate exam and procedure name mapping is critical for DIR participating facilities to gain insight into their radiation dose levels overall and to obtain accurate comparisons with national benchmarks to drive quality improvement. The Exam Name Mapping Resource Guide helps personnel at facilities participating in the DIR understand the ins and outs of exam and procedure name mapping.  The guide links together Knowledge Base articles that dive deeper into mapping details and may be especially helpful for staff members new to exam name mapping to become familiar with important considerations to ensure your facility obtains the most value from your DIR participation.

In the All About Mapping webinar held April 21, 2022, learn from national experts about mapping methods for CT and fluoroscopy and best practices and pitfalls to avoid. Below are answers to user questions from that webinar.

• SET UP AND ROLES
• LEXICON
• MAPPING TOOLS AND PROCESS
• MAPPING ERRORS
• MAPPING BEST PRACTICES
• DIR LINK
• DIR MODALITIES

SET UP AND ROLES

How do you determine which type of user you are and how do you change it?

You can go to "My Account" on the main NRDR menu, open "change account details," and see what user profile role(s) you have. In many cases, only the Corporate Account Admin or Facility Admin can update user roles. However, a Registry Admin can also update some user roles. Please refer to the chart in the Accounts and Profiles Knowledge Base (KB) article.

Can multiple people be Facility Admins or is only one person allowed?

There can be only one Facility Admin per facility, but a corporate account with multiple facilities can have multiple Facility Admins.

Can Service Users map on the corporate level?

Yes, Service User is the role you want to assign to almost anyone who is mapping, as most sites should map at the corporate level. Reference the Accounts and Profiles KB article for more information on each role’s permissions.

What role should medical physicists who need access to map be assigned?

Depending upon a medical physicist’s involvement in the DIR, they could have multiple roles. For example, if their role is primarily to perform mapping either at the corporate or facility level, they could have a Service User role. If they oversee the management of the DIR, they could have a Corporate Administrator or Facility Administrator role. 

What are some ways in which multi-facility institutions manage the mapping process?

See All About Mapping Webinar recording (starting at 18:59).

What is the purpose of the “change facility” button on the mapping screen if corporate-level mapping supersedes facility-level mapping?

You can map at the facility level if the structure of your system warrants it and you have set up the corresponding settings for your facility. However, the general recommendation is to map at the Corporate Account level unless you have discussed it with other users, especially the Corporate Account Administrator. See the KB article about Exam and Procedure Name Mapping Settings for more information on how to manage these settings.

LEXICON

What is ACR Common and where can I find a list of terms and their mapping to RPIDs?

ACR Common is a radiology procedure ontology, and you can see and download all current data on acr.org here.

MAPPING TOOLS AND PROCESS

What options do DIR participants have for mapping their exams?

Check out the following resources:

• All About Mapping Webinar recording (starting at 22:16)
• Using the Exam Name Mapping Tool and Using the Mapping Tool’s Export and Upload Functions
• A six-minute video overview about mapping CT exams  

What are some examples of how active sites use the different mapping methods?

See the All About Mapping Webinar recording (starting at 25:34).

How does ACR perform the mapping match process? Is it based on an exact match or on a keyword match? Example: CT Abd/Pelvis = CTABDPELVIS = CT abd pelvis = CT Abdomen Pelvis?

It is currently a mix of the two. The ACR uses historical mapping to find mapping for a study description and do exact match to new exams to suggest a mapping. So while we do not do a formal keyword match, the size of our database gives us enough exact matches that most keywords are covered. Going forward, we are exploring machine-learning based processes to map probabilistically to metadata (eg, body part, modality modifier, contrast use) as well as to ACR Common names.

MAPPING ERRORS

What are some of the most common mapping errors you’ve seen and what advice do you have for sites to avoid those errors?

See the All About Mapping Webinar recording (starting at 29:40) and Tips for Exam and Procedure Name Mapping Maintenance.

If an exam is mapped incorrectly when it is mapped automatically based on exam description, what is the best method to correct this?

You can resolve the erroneous mapping via the Exam Name Mapping Tool or using the Mapping Tool’s export and upload functions.

If we find (and correct) studies originally mapped incorrectly, do those prior studies get re-aggregated after the correction for future reporting?

Generally speaking, all prior studies are re-aggregated. For some reports, the re-aggregation is performed only for exams in the last three years – all other reports will be re-aggregated for all submissions. Current reports with the 3-year limitation include CT Standardized Dose Index Reports, CT Facility Comparison, CT Facility Summary, and CT Dose Info by Exam.  All Fluoroscopy reports are fully re-aggregated.

Why is the mapping I performed a day before not saved when I view it later?

There’s a 24-hour delay before changes to your mapping will be reflected in the database. You will see changes in the Tableau (online) report within two business days. 

MAPPING BEST PRACTICES

How often do you advise reviewing and updating your mapping?

For the first few months after starting to send data to the DIR, it is recommended to check your mapping on a weekly basis. After that, it can be done on a monthly and then quarterly basis. We suggest keeping to a quarterly schedule in the long term because changes to protocols usually occur slowly over time, but there are occasions when there may be wholesale changes to exam names which can result in many new names to map. 

Do you have any advice for how to map a protocol that has multiple exams on one dose report? Our ER has protocols built to make workflow easier such as head/c-spine for trauma.

RadLex has trauma specific RPIDs (including head/c-spine), and trauma protocols should be mapped as such. This is because it's so common for acquisitions to be added on during trauma cases which will distort analytics for "routine" imaging. For head/c-spine protocols, be aware that the DIR processes the dose index data at the exam level, so all acquisitions will be normalized to one of the two CTDI phantom sizes (16 or 32cm). It's standard practice to report head/c-spine data using the 32cm phantom, so the head series will be normalized to 32cm phantom (dose indices will be divided by 2.3). If you create a head-c-spine protocol by adding a c-spine series to your routine head protocol, all dose indices will be normalized to the 16cm phantom, i.e., they will be multiplied by 2.3, and you will see outliers in your data. See also All About Mapping Webinar recording (starting at 55:33).

What do you suggest for mapping pediatric exams? 

RadLex used to have pediatric specific RPIDs, but from an analysis perspective, it doesn't matter if you map to pediatric specific RPIDs or general ones; the DIR treats them the same way. The general recommendation is to map to the correct RPID and the analysis by age happens on the back end.

How do I map unwanted exams and are they excluded from quarterly aggregate feedback reports?

See the All About Mapping Webinar recording (starting at 44:03).

How can I assign the "Unwanted" tag to protocols my institution receives from an outside third party for which our physicians read images? I have no control over the scanner/protocols, but the RDSR/dose info is sent to the registry.

You can do either of the following:

1. Map them to Unwanted in your mapping. See Using the Mapping Tool’s Export and Upload Functions for specific instructions.
2. Work with your PACS team to filter out OSF from being forwarded to TRIAD. If Station Name is populated in the metadata for your exams, you can try filtering using that. See also the All About Mapping Webinar recording (starting at 51:32).

What happens when a device physically moves from one facility to another facility within the same Corporate Account? If the Station Name is constant but the Scanner-Facility Mapping in TRIAD is updated, what happens to the legacy/pre-relocation data? What facility does it show up as in reports?

Exams that were previously submitted under the former facility will show up in reports associated with the “old” facility. Exams submitted going forward will show up associated with the new facility. If the desire is to have the old exams show up as part of the new facility, you would need to work with ACR to have those reassigned

Is 403 the most common RPID for lung cancer screenings?

The registry does not specifically capture the indication for the exam; however, based on exam descriptions that include “Lung Cancer Screening,” the most common RPIDs used are:

1. RPID1377      CT CHST LO DOSE SCREEN
2. RPID150        CT CHST LO DOSE CANCER WO IVCON
3. RPID403        CT CHST LO DOSE WO IVCON

Does the presence of both RPID22 and 265 create a modeling problem? What do I do when there are duplications? 

The DIR aggregates multiple RPIDs into a single bucket for dose reporting and comparison purposes.  For example, RPID22 and 266 roll up into CT Brain w/o contrast in the DIR. RadLex and ACR Common undergo routine maintenance and updating, but inconsistencies or duplications occur from time to time. Using "RPID Short Name" for analytics helps us get around this a little bit by lumping together the same or very similar RPID exams that have numbers that have changed across RadLex Playbook versions. See also the All About Mapping Webinar recording (starting at 47:20).

Within the DIR are the terms "procedure,” "exam,” and "study description" interchangeable? If so, can one term be used consistently or is there a KB article about the distinctions?

Study Description and Requested Procedure Description are both facility-generated free-text fields in the RDSR and DICOM header. How a facility populates either or both in the RDSR (and DICOM header) varies depending upon a variety of workflow and software considerations.  While the terms “procedure” and “exam” tend to be used interchangeably in the ACR’s Knowledge Base articles, generally, the term “exam” is used with CT and x-ray modality records, and the term “procedure” is used with interventional fluoroscopy records. 

DIR LINK

How will DIR Link – the next generation of TRIAD – impact mapping?

See All About Mapping Webinar recording (starting at 36:20).

How will scanner filtering in TRIAD be handled when changing to DIR link?

DIR Link will have similar scanner mapping processes as are currently available in the TRIAD Site Server. Any existing scanner mappings in TRIAD will be ported/transferred to DIR Link.