The SCAN Initiative

The SCAN initiative is a collaboration between NACC, UC Berkeley, Mayo Clinic, University of Michigan, UC Davis, and LONI, and is funded by the National Institute on Aging. The goal of SCAN is to promote standardization of PET and MR image acquisition so that images can be combined across multiple centers.

For more information about the SCAN initiative, please visit

*Please note that the SCAN initiative does not accept non-SCAN compliant MRI and PET images.

Existing MRI and PET images collected before January 1, 2021, and prospective images that don't meet SCAN protocol are still accepted by NACC - learn more here

scan pipeline

Pipeline for standardized MRI/PET data collection, harmonization, analysis, and sharing.

The SCAN Dashboards

This dashboard tracks the number of SCAN-compliant MRI/PET images and the number of participants that images have been submitted for by each Alzheimer's Disease Research Center to LONI/NACC. Learn more about the Dashboard.

New to the SCAN Dashboards?


Please note: Only ADRC members with data access privileges can view the ADRC-Specific SCAN QC Dashboards. Learn how to get access in the SCAN Dashboard Quick Guide below.

About the SCAN Dashboards

About the SCAN Public Dashboard

The SCAN Public Dashboard tracks the number of participants with SCAN-compliant MRI and PET images and the total number of images submitted by each Alzheimer’s Disease Research Center (ADRC) to SCAN. This resource is meant to provide ADRCs and researchers with up-to-date information on the number of standard images that are available for analysis.

Information included in the Dashboard:

  • Links to each centers ADRC-specific SCAN QC Dashboard
  • Total # of MRI and PET participants for whom the site has submitted data to SCAN
  • Total # of standard MRI exams and series submitted to SCAN that are available for analysis
  • Total # of PET scans (amyloid or tau) submitted to SCAN that are available for analysis

Information not included in the Dashboard:

  • SCAN analysis data for ADRCs
  • SCAN analysis data for Researchers: ADRD researchers around the world may access this data via NACC's Quick Access File beginning in late 2023.
  • ADRC-specific PET and MRI data: The MRI and PET summary and QC status information is available through the ADRC-specific SCAN QC dashboards
  • Data for participants without existing NACCIDs: For the time being LONI will only be accepting data submissions for participants who have existing NACCIDs

About the ADRC-Specific SCAN QC Dashboards

Each ADRC can access their ADRC-specific SCAN QC dashboards via the SCAN Public Dashboard located above. The ADRC-specific SCAN QC dashboards will:

  1. Enable them to track the QC status of their MRI and PET submissions, allowing them to rapidly address errors.
  2. Serve as an auditable record of all SCAN MRI data submitted to SCAN by a given ADRC, downloadable as a csv file.

IMPORTANT NOTE: The ADRC-specific SCAN QC Dashboards are only available to ADRC members.

Information that will be included in the ADRC-specific SCAN dashboards includes:

  • All PET summary and QC data submitted by each ADRC including:
    • NACCIDs
    • PTIDs
    • PET study date and time
    • image UID, scanner model
    • PET radiotracer used
    • whether the scan passed QC or not
    • QC comments (why the scan failed QC, if failed)
  • All MRI summary and QC data submitted by each ADRC including:
    • NACCID
    • PTID
    • MRI study date and time
    • Image UID
    • Scanner model
    • Series date and time
    • Series number
    • Series type
    • Study comments: Visual artifacts, etc.
    • Release for Analysis: Whether the series was released for analysis or not based on QC and protocol checks

The LONI uploader will include a new verification step

Beginning July 29, 2023 the LONI imaging data submission interface will require that sites enter both the PTID and the NACCID for a given participant to submit their MRI/PET data to SCAN. This change was introduced to ensure NACCID and data fidelity for the SCAN initiative. As shared in our ADRC-wide communication on March 17, 2023, ADRCs are currently only able to submit SCAN data for participants with existing NACCIDs. More details about this temporary limitation and next steps can be found in the What is the current process for submitting MRI/PET images? section of this page.

How to correctly submit your data via the new LONI uploader

  • Sites must enter both identifiers into the Subject ID text field using the convention PTID+NACCID, where PTID and NACCID are separated by the + character.

    • If the given PTID and NACCID pair match the record present in the NACC database, the upload process will be allowed to continue.

    • If not, then the user will receive an error message indicating that the PTID and NACCID combination are not valid, and the upload will not be allowed to continue.

  • Users who do not follow the PTID+NACCID convention will see a message describing the expected formatting of the Subject ID.

How do I find the NACCIDs for my participants?

To access your site’s PTID and NACCID pairs, please work with your site’s data manager to utilize the “PTID to NACCID Map” tool available via the NACC portal.

For detailed instructions, please see the PTID to NACCID Map Instructions here.

The SCAN MRI and PET manuals linked on the webpage have been updated to reflect this change and provide your site with instructions on how to submit data using the new LONI uploader.

When and how will SCAN summary data be returned to the ADRCs?

We anticipate that SCAN data will be returned to sites in Fall of 2023.

All ADRCs that have contributed data to SCAN were asked to perform a data audit for their SCAN submissions in March of 2023. Now that the SCAN data audit has been completed by all ADRCs, NACC and SCAN are working to return SCAN summary and analysis data (SUVRs and volumes included) to each ADRC via REDCap. If you have questions about the SCAN data audit, please contact

In the future, SCAN summary data will be available to ADRCs in real-time in addition to your UDS data via the site-specific ADRC portals hosted in NACC's new data repository.Anticipated availability is Winter 2023/2024.

Data Front Door overview
New NACC Data Platform

What is the current process for submitting MRI/PET images?

As of March 17, 2023, sites will only be able to submit SCAN MRI and PET images to LONI for participants that already have a NACCID. This change will prevent errors (i.e., duplicate NACC IDs for participants, etc.) from being introduced into the database and the need for future SCAN data audits. See Changes to the LONI Uploader section for more information.
Please note that this is a temporary change. Sites are encouraged to continue collecting SCAN data on all of their participants but will not be able to submit data for participants without existing NACC IDs until a new process for assigning NACCIDs to SCAN participants is put in place. NACC hopes to provide further updates to ADRCs on this new process soon.

What about non-SCAN compliant MRI/PET images that are submitted to NACC?

As of March 17, 2023, sites will only be able to submit non-standard (non-SCAN compliant) MRI and PET images to NACC for participants that already have pre-existing NACCIDs.

Please do not submit non-standard MRI and PET images to SCAN as the SCAN initiative only collects SCAN-compliant MRI and PET images. Existing MRI and PET images collected before January 1, 2021, and prospective images that don't meet SCAN protocol are still accepted by NACC.

Learn more about submitting this data to NACC here.

How are identifiers used for the SCAN data?

When submitting MRI/PET images to SCAN via the LONI uploader, you are currently asked to enter the Subject ID or PTID. This number is different from the NACCID as described below:
  • Subject ID or PTID: this is the ADRC-managed participant ID, or "local ID". Formats vary by ADRC.
  • NACCID: this is the NACC-managed participant ID. It is a string with the prefix 'NACC' followed by 6 digits.
  • ADCID: this is the NACC-managed center ID. This is a two-digit number.
Each PTID and ADCID pair maps to a unique NACCID.

How are MRI and PET imaging submissions from ADRCs currently being tracked?

SCAN-compliant MRI/PET images submitted to LONI as part of the SCAN initiative:

  • SCAN Public Dashboard: The Public SCAN Dashboard tracks the number of SCAN-compliant MRI/PET images and the number of participants that images have been submitted for by each ADRC to SCAN.
  • ADRC-Specific SCAN QC Dashboards As part of the ADRC Portals, each ADRC will have access to their ADRC-specific SCAN QC dashboards that will a) enable them to track the summary and QC status of their MRI and PET submissions, allowing them to rapidly address errors, and b) serve as an auditable record of all SCAN MRI data submitted to LONI/NACC by a given ADRC, downloadable as a csv file.
  • The NACC monthly reports for each ADRC do not include the MRI/PET images submitted to LONI for the SCAN project in the image counts. We will not be adding SCAN images to these static monthly reports because we are in the process of modernizing the NACC Data Platform and complete SCAN-compliant image counts will be available through the SCAN dashboards.

Non-SCAN compliant MRI/PET images submitted to NACC:

  • NACC is currently in discussion with NIA and the Imaging Steering Committee to determine how legacy MRI and PET images will be tracked and reported at NACC as we transition to our modern Data Platform and ADRC portals.
  • Your monthly report should currently reflect the correct number of legacy MRI and PET images that have been submitted to by your site to NACC.
  • There were previously some errors in these counts due to a bug. However, we believe all errors with counts of images at NACC have now been corrected. If you experience an error, please reach out to

How will MRI and PET imaging submissions be tracked in the future?

As NACC completes its transition onto our new modern data platform, we will launch the following resources:
  • ADRC Portals

    The ADRC Portals will provide ADRCs with self-service access to view, download, and audit their real-time data. These portals will replace inefficient static monthly reports with modern real-time ADRC-specific data portals (ADRC Portals), fulfilling an emergent request from ADRCs to have better access to their data submissions.

    The ADRC Portals will provide ADRCs with access to six core data/metadata types:

    • UDS
    • Neuropathology
    • Non-standard MRI/PET
    • Standard MRI/PET
    • Biospecimen (NCRAD) and Genetic/genomic (NIAGADS)
    • Participant Diversity Metrics

    NACC is currently working to build the ADRC Portals within NACC's new Data Platform (powered by Flywheel). Flywheel will support the need to make this data accessible only to designated ADRC representatives, requiring management by ADRC personnel and the technology platform to allow access control for appropriate viewers. NACC is using user centered design to develop dashboards to adapt the Flywheel interface to the ADRC programs' unique needs.

    Data Portal overview
    Overview of the ADRC Data Portals that will allow for each center to have self-service access to their patient UDS, neuropathology, non-standard MRI/PET, diversity metrics, ADRC standard MRI/PET, and specimen/marker/genetic metadata.
  • NACC's new Data Platform

    The NACC Data Platform (NACC DP) that will integrate a host of existing and new standardized and longitudinal data streams from across the ADRC Program as well as metadata and analysis from partner organizations and initiatives, with all data streams linked by NACC Identifiers (NACC IDs). The NACC DP will include a variety of data search and access interfaces including the Data Front Door, ADRC Data Portals, and the NIA Portal.

    These systems have been designed with an eye towards needing a modern tools that will not only accommodate our existing long-standing data streams such as the Uniform Data Set (UDS), neuropathology reports, and non-standard MRI/PET but that will also scale to accommodate and share innovative new data streams such as standardized imaging data, digital neuropathology, and digital biomarkers, and that can integrate complementary metadata and analysis data for standardized MRI/PET imaging (SCAN/LONI), genetic/genomic (NIAGADS) and biomarker (NCRAD) data from other ADRD data repositories, with all data streams linked by NACC unique identifiers (NACC IDs).

    The transition to this new data platform will begin by giving access to ADRC portals in which each center will be able to access their data and view dashboards allowing them to track their contributions to the ADRC program. NACC will increasingly add functionality to these portals, ultimately replacing old processes like emailed monthly reports.

How will ADRCs who contribute data to SCAN be acknowledged?

NACC will build off the current NACC Data Use Agreement (DUA) policy to provide researchers with a comprehensive list of ADRCs and other related grants who have contributed their data to SCAN. All researchers and person(s) requesting data from NACC (including SCAN data in the future) must accept the NACC DUA policy.
The current NACC DUA policy requires authors to include the following statement acknowledging the NACC grant and Center support in presentations and the acknowledgments section of manuscripts:

“The NACC database is funded by NIA/NIH Grant U24 AG072122. NACC data are contributed by the NIA-funded ADRCs: P30 AG...., etc.”

If your site is involved in the SCAN initiative and you have additional grants or updates to include in the acknowledgements, please reach out to

How and when can researchers access SCAN data?

SCAN Summary and Analysis Data (Volumes and SUVRs) via NACC's Data Front Door

Phase 1: Researchers will be able to access SCAN data through the NACC Quick Access File data request system. We anticipate that this will be available by Winter 2023/2024.
NACC's Data Request System - learn more here
  • NACC currently provides UDS, neuropathology, and non-SCAN compliant MRI/PET data to researchers anywhere through our Quick Access File
  • It takes ~15 minutes for researcher to submit a data request
  • Researcher must sign a Data Use Agreement to access this data (NACC's current Data Use Agreement)
  • NACC has distributed more than 220 Quick Access Files since May 2022
Phase 2: NACC’s Cohort selection, data visualization, and access tool
  • Allows self-service cohort selection
  • Provide the ability to download raw data directly

Request SCAN Raw Images via NACC's Data Front Door

SCAN MRI/PET images will be made available by LONI. NACC will provide updates on the availability of raw images as progress is made by SCAN, LONI, and NACC to ensure raw image data is de-identified before it is made available to the public.