Question: When we need to override an edit pair that CCI lists in the "mutually exclusive" table, which code takes modifier 59 -- the column 1 or column 2 code? Iowa Subscriber Answer: According to CMS instruction, you should append modifier 59 (Distinct procedural service) to "the secondary, additional, or lesser procedure(s) or service(s)." See Chapter 23 of the Claims Processing Manual (Internet Only Manual 100-04), Section 20.9.1.1.B. The Correct Coding Initiative (CCI) places edit pairs in two different tables -- "column 1/column 2" and "mutually exclusive." CCI used to call the former "comprehensive/component" edits, and that name still describes the relationship of most edit pairs in the column 1/column 2 table. In other words, the column 2 code is usually the "lesser" procedure that CCI considers a component of the more "comprehensive" column 1 service. For the mutually exclusive table, however, the "lesser" service (in terms of RVUs) may be in column 1. For instance, CCI lists 88104 (Cytopathology, fluids, washings or brushings, except cervical or vaginal; smears with interpretation) in column 1 of the mutually exclusive edit table paired with 88173 (Cytopathology, evaluation of fine needle aspirate; interpretation and report) in column 2. Note: Some coding experts advise that you always append modifier 59 to the column 2 code. You should check with your payers to ensure that you-re using the modifier according to their instruction.