Part D File Information

There are multiple files that are associated with the Part D data:

  • Part D Drug Event File (PDE) DocumentationExternal Web Site Policy - This file includes all transactions covered by Medicare prescription drug plan for both Prescription Drug Plans (PDPs) and Medicare Advantage Prescription Drug Plans (MA-PDs).
    • Drug Characteristic FileExternal Web Site Policy - variables appended to the PDE that describe the drug listed (e.g., NDC, brand and generic name)
  • Plan Characteristics FileExternal Web Site Policy - contains Medicare Advantage plan and Prescription Drug Plan information separated into six subfiles: base/benefit file, premium file, cost sharing tier file, service area file, special needs plans file, and multi-year crosswalk file. The information in the Plan Characteristics File can be linked to the PDE and the MBSF files (using contract and plan identifiers) to assess for variation in utilization and costs by plan type.
    • NOTE: The Multi-year Crosswalk File allows the same contract-plan to be tracked across years (Part D: 2007+; Part C 2015+), because contract and plan identifiers can change on an annual basis. The relationship code and relationship description variables clarify if a contract-plan in the reference year is new, renewal, consolidation, or termination. This annual file will include encrypted identifiers for years prior to 2015 and unencrypted identifiers for 2015 and later.
    • NOTE: The Plan Bridge File provides a crosswalk between the encrypted and unencrypted contract and plan identifiers; in 2015, CMS began releasing unencrypted contract and plan identifiers.
    • NOTE: The Multi-year Crosswalk File and Plan Bridge File can be used together to track plans across time (e.g., if a plan used one, encrypted identifier in 2010 but then switched to a new plan identifier in 2011, use the annual Crosswalk File 2010-2011 to find that change. Then use the Plan Bridge File to link this encrypted plan identifier to its unencrypted plan identifier and then the annual Crosswalk File again to track the same plan after 2015.
  • Formulary File DocumentationExternal Web Site Policy - suite of three subfiles: formulary, excluded drug and Over the Counter Drug that contain information on how the plan covers the prescription drugs filled.
  • Pharmacy Characteristics File DocumentationExternal Web Site Policy - contains information about the pharmacy identified as the source of the drug for each PDE prescription fill record.
    • Pharmacy Bridge FileExternal Web Site Policy - In 2014, CMS changed the pharmacy identifier included on the PDE changed, this file provides a crosswalk that allows tracking the same pharmacy across this transition year.
      • NOTE: Although one can track the same pharmacy over time, all pharmacy identifiers are encrypted.
  • Prescriber Characteristics File DocumentationExternal Web Site Policy - contains descriptive information for the prescriber identified in the PDE file.

View CCW’s Medicare Claims Record Layout and CodebookExternal Web Site Policy

Last Updated: 17 Oct, 2023