Author: Lori Carlin, CPC, COC, CPCO, CCS, CRC


Author: Angela Wood, CPC
Senior Physician Auditor / Educator


(303) 801-0111

One of the best resources we frequently recommend to providers is the National Correct Coding Initiative (“NCCI”) policy manual. It is like using a crystal ball to peer into the mind of CMS. The policy manual explains why CMS has edits that bundle two codes together, or why CMS limits how many units of a particular code you can bill. More importantly, the manual explains when it is appropriate to override these edits and how to do it correctly.

This manual serves as a toolkit for providers, coders, and billers alike.  We recommend dedicating specific time to read chapter one “General Correct Coding Policies.”  This chapter is packed full of very helpful information about edits and could easily be used for discussion topics between colleagues or as the basis for educational sessions.

There are three main NCCI edit types:

  • procedure to procedure (“PTP”) edits
  • medically unlikely edits (“MUE”)
  • add-on code (“AOC”) edits.

In this article series, we will cover all three of the edit types and give you strategies on how to address them. Probably the most familiar of these edits are PTP edits. These edits indicate when a pair of codes should not be billed together. In our next article, we will discuss PTP edits in detail.

To download a copy of the NCCI policy manual, click the link in the references section below.

Keeping up with the nuances of NCCI edits can be exhausting. PERCS is here to help you navigate guidelines to remain compliant. If you have any questions or need assistance, please contact Angie Wood, CPC, Sr. Physician Auditor and Educator at or Lori Carlin, CPC, COC, CPCO, CCS, CRC, Principal, at They will be readily available to answer your questions and provide expert advice, so you are well equipped to move forward!