#941 - NLST - RESOLVED
Dear CDAS team,
I am writing to inquire about two related data completeness questions regarding the open NLST CT imaging data set (the full, publicly available collection as provided via TCIA/IDC).
We have observed two patient count discrepancies in the CT arm:
Imaging Discrepancy: Our analysis shows imaging data for 26,254 patients, fewer than the 26,722 patients reported in the total imaging cohort publications.
Cancer Patient Discrepancy: Clinical index of the IDC shows 1,089 CT cancers (which matches the NLST user guide), but IDC/TCIA provide CT images for 1,061 of them; the remaining ~28 have no CT imaging objects in IDC/TCIA.
- Both the IDC CT index and the manually downloaded TCIA manifest contain exactly the same 26,254 CT patients and 1,061 CT cancer patients—no downloads are missing on our side.
Could you please clarify the status of these missing patients? Specifically, are these cases where clinical data exists but the images are not publicly available, or is there another route to access the full and complete cohort numbers?
For additional context on our specific findings, please see the discussion here: https://discourse.canceridc.dev/t/nlst-data-completeness-missing-28-ct-cancer-patients/765/2
Thank you for your time and guidance.
Sincerely,
Kosmas Galanis
I am writing to inquire about two related data completeness questions regarding the open NLST CT imaging data set (the full, publicly available collection as provided via TCIA/IDC).
We have observed two patient count discrepancies in the CT arm:
Imaging Discrepancy: Our analysis shows imaging data for 26,254 patients, fewer than the 26,722 patients reported in the total imaging cohort publications.
Cancer Patient Discrepancy: Clinical index of the IDC shows 1,089 CT cancers (which matches the NLST user guide), but IDC/TCIA provide CT images for 1,061 of them; the remaining ~28 have no CT imaging objects in IDC/TCIA.
- Both the IDC CT index and the manually downloaded TCIA manifest contain exactly the same 26,254 CT patients and 1,061 CT cancer patients—no downloads are missing on our side.
Could you please clarify the status of these missing patients? Specifically, are these cases where clinical data exists but the images are not publicly available, or is there another route to access the full and complete cohort numbers?
For additional context on our specific findings, please see the discussion here: https://discourse.canceridc.dev/t/nlst-data-completeness-missing-28-ct-cancer-patients/765/2
Thank you for your time and guidance.
Sincerely,
Kosmas Galanis
Discussion
Status Changed from Open to Resolved.
Hello Kosmas,Of the 26,722 participants, images were only received for 26,254. Similarly, although we have 1,089 cancers in the CT arm, we only have images for 1,061 of them. Does this answer your question?
Regards,
Doug
Status Changed from Resolved to Open.
That's exactly what I was looking for! Thank you so much.Status Changed from Open to Resolved.
Contribute to this Discussion
CDAS staff and the ticket creator will be notified of comments you submit below.
Since you are not logged in to CDAS, we ask that you provide your name and email when submitting new comments on this page. If you log in, you will not need to enter this information.