(6) Definitions For purposes of this subsection: (A) Eligible professional; covered professional services The terms “eligible professional” and “covered professional services” have the meanings given such terms in subsection (k)(3). (B) Physician reporting system The term “physician reporting system” means the system established under subsection (k). (C) Reporting period (i) In general Subject to clauses (ii) and (iii), the term “reporting period” means— (I) for 2007, the period beginning on July 1, 2007 , and ending on December 31, 2007 ; and (II) for 2008 and subsequent years, the entire year. (ii) Authority to revise reporting period For years after 2009, the Secretary may revise the reporting period under clause (i) if the Secretary determines such revision is appropriate, produces valid results on measures reported, and is consistent with the goals of maximizing scientific validity and reducing administrative burden. If the Secretary revises such period pursuant to the preceding sentence, the term “reporting period” shall mean such revised period. (iii) Reference Any reference in this subsection to a reporting period with respect to the application of subsection (a)(5) (a)(8) shall be deemed a reference to the reporting period under subsection (a)(5)(D)(iii) or the quality reporting period under subsection (a)(8)(D)(iii), respectively.