CDT (CDT) - Metathesaurus Representation

Summary of Changes

There were no changes to the original file format. Minor changes were made to the assignment of CODE and SCUI values of atoms with TTY = "HT"

Notes:

• In the printed CDT book, some codes appear out of order. The order information is not available in electronic form, therefore the UMLS hierarchy varies slightly from the hierarchy in the printed book.
• A value of "None" in the original data is treated the same as a blank or null value.
• CDT in the Metathesaurus is extracted from a file provided by the American Dental Association (ADA). The Metathesaurus also includes the HCPCS version of CDT, which has RSAB = "HCDT." The CDT hierarchy is created from the data file provided by the ADA, while the HCDT hierarchy is created during Metathesaurus production using analysis of the HCPCS printed manual.

Source Provided Files:

File Name	Description
CDT 2023 ASCII Tab Delimited_2022May17.txt	Documentation and tab-delimited data (the data is also available from the ADA as an Excel file)
ReadMe_CDT 2023_6.3.22.pdf	Documentation

Identifiers:

Identifiers are assigned as follows:

• CODE:
• • TTY = PT, TTY=OP: the value of the Code field from tab-delimited data file
  • TTY = HT: A range, e.g. "D4210-D4999," indicating the high and low code values encompassed by the HT. This value is computed during Metathesaurus source processing. "Split" ranges are separated by a comma. For example:
    
    • EXCISION OF SOFT TISSUE LESIONS: D7410-D7415,D7465-D7465
    • EXCISION OF INTRA-OSSEOUS LESIONS|D7440-D7461
• SAUI: Not applicable
• SCUI: Same as CODE
• SDUI: Not applicable

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