The most common reasons a claim may be denied:

Duplicate claim:

• Service was performed multiple times on the same day, but submitted on separate claims or separate line items, and did not include appropriate modifiers 76 or 77.

Medical necessity for policy related topics:

• Local Coverage Determinations
• Podiatry L33636 and A57759
• Physical Therapy L33631 and A56556

Medically unlikely edits and correct coding initiatives:

• Medically Unlikely Edits
• National Correct Coding Initiative

Modifier KX for use with physical therapy:

• KX Modifier Threshold
• KX appropriate when patient qualifies above the threshold under the exception regulations. These should not be reopenings. Providers are required to pre-calculate up to the therapy cap and submit claims with the KX modifier.
  • CMS Internet-Only Manual, Publication 100-04, Medicare Claims Processing Manual, Chapter 5