_dta:
  1.  additional_changes20092 set up by Jean Roth , jroth@nber.org , 8 Jan 2016

ndc:
  1.  The National Drug Code (NDC) serves as a universal product identifier for human drugs and biologics.
  2.  Each NDC must be reported as an 11-digit code unique to the manufacturer of the specific drug or product.

ndc13:
  1.  The National Drug Code (NDC) serves as a universal product identifier for human drugs and biologics.
  2.  Each NDC must be reported as an 11-digit code unique to the manufacturer of the specific drug or product.

hcpcs:
  1.  HCPCS codes are used by Medicare and monitored by the CMS .
  2.  HCPCS Level II codes are assigned to every service a medical practitioner provides
  3.  to a Medicare patient including durable medical equipment, prosthetics and orthotics supplies.
  4.  These codes are an alpha character followed by four numbers.

  obs:            59                          
 vars:             7                          8 Jan 2016 16:51
 size:         5,900                          (_dta has notes)
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              storage   display    value
variable name   type    format     label      variable label
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ndc             str11   %11s                * National Drug Code (NDC)
ndc13           str13   %13s                * National Drug Code (NDC) with Dashes
hcpcs           str27   %27s                * Healthcare Common Procedure Coding System (HCPCS)
change          str21   %21s                  Change
oldvalue        str1    %9s                   Old Value
newvalue        str1    %9s                   New Value
commentorexplanation
                str26   %26s                  Comment or Explanation
                                            * indicated variables have notes
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Sorted by: ndc  hcpcs  change  newvalue