NLST Images -- General Details
Dates
The Study Dates are fictitious. While appearing real, they are coded to represent the 3 screening years:
- 19990102 -- Screening Year 0
- 20000102 -- Screening Year 1
- 20010102 -- Screening Year 2
Patient Identifiers
The Patient Identifiers (PIDs), in DICOM tag (0010, 0020) Patient ID, are 6 digit random numbers assigned by IMS. They are called IMS-Global-IDs. PIDs beginning with '1' are LSS images; those beginning with '2' are ACRIN images.
Prior ACRIN and LSS PIDs may be found in 2 DICOM tags: (0010, 1000) Other Patient IDs and (0013, 0040) Clinical Trial Subject ID. These prior PIDs are random 5-digit (ACRIN) or 6-digit (LSS) numbers that contain no screening site information; the LSS prior PIDs may have leading zeroes which may or may not appear unless specified that they do so.
Patient Names
Patient Names appearing in DICOM tag (0010, 0010) are a construct from the participant's prior PID concatenated with a caret and the string 'ACRIN' or 'LSS'; examples:
- 54321^ACRIN
- 123456^LSS
Series Descriptions
These consist of 11 coded comma-separated values, listed below. Code value descriptions may be found in the attachment Series-Description-Details.xlsx.
- (1) Screening Year
- (2) Image Type
- (3) Manufacturer
- (4) Scanner Model
- (5) Convolution Kernel
- (6) Reconstruction Diameter
- (7) Slice Thickness
- (8) kVp
- (9) mAs
- (10) Effective mAs
- (11) Slice Thickness