2006 proposed fee schedule - American Society of Clinical Oncology

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contain a core population plus adjacent areas that reflect a
high degree of social and economic integration. This
integration is measured by commuting patterns, thus
demonstrating that the areas likely draw workers from the
same general locale. In addition, the CBSAs reflect the
most up-to-date information, based on the 2000 Census. OMB
reviews its metropolitan area definitions preceding each
decennial census to ensure consideration of the most recent
population changes. Finally, in the context of the IPPS, we
have reviewed alternative methods for determining geographic
areas for purposes of the wage index. In each case, we have
concluded that it was preferable to retain the independently
developed OMB designations rather than replace them with
alternatives. (See the August 11, 2004 final IPPS rule at
69 FR 49027-49028.)
Aside from the long established precedent of using OMB
geographic designations to adjust for differing area wage
levels in the PPSs that we administer, we also point out
that the Congress has recognized the propriety of the OMB
definitions in distinguishing among geographic areas for
making Medicare payments. For example, section
1886(d)(2)(D) of the Act defines an “urban area” as “an area
within a MSA (as defined by the OMB) or within a similar
area as the Secretary has recognized.” Similarly, in the
sections of the Act governing the guidelines to be used by