Medicare Part D Event file: Utilization Management Variables

Formulary linkage and Variable Differences between 2006-09 and 2010-forward files

Medicare Part D Event file: Utilization Management Variables

Current Version Date: 

Purpose: Part D Event (PDE) files for data years prior to 2010 may include the values of “XX” or “NA” for any of the four Utilization Management variables. This article describes when and why each value was used. 


The Part D event file for 2006 through 2009 included the Utilization Management (UM) Variables

  • prior authorization
  • quantity limit
  • tier
  • step therapy


Beginning with the 2010 Part D data, these variables are included in the Part D Formulary Characteristics File.


Part D data 2006-09 formulary linkage

The contract ID and plan ID on the PDE were matched to the plan characteristics base file to get the corresponding formulary ID.  The PDE record’s National Drug code (NDC or PROD_SRVC_ID) was converted to brand name/clinical formulation ID using the proprietary First Databank database.  The same conversion process was applied to the proxy NDC from CMS’s Health Plan Management System (HPMS) formulary data (source data).  Linkage was attempted by matching both the source data and PDE using formulary ID and brand name/clinical formulation ID.  If a match existed then the UM variables were populated on the PDE.



Plans that dropped during the year could not be matched, since the PDE 2006-09 files were processed as year-end snapshots. Then the value of “XX” was assigned to the UM variables. A value of “NA” was assigned to unlinked cases when the NDC from the PDE record did not match a drug on the plan’s formulary. This could have happened for one of two reasons:

  • the NDC on the PDE was for a generic drug product and if the Part D plan submitted a particular branded version different from the name in the First Data Bank data base that CCW uses, then the drugs were not linked and the UM variables were flagged “NA”.
  • HPMS, the source system of the plan information only included one version of the plan formulary; if it changed during the year, a match could not be made.


Additional Resources: 
PDF icon CCW Part D Data User Guide333.75 KB
ResDAC is grateful to staff of General Dynamics Information Technology for their assistance with the topic of this article.
Article Number: 
This work was performed under CMS Contract Number HHSM-500-2005-00027I.
Related Data File Families: 


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