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Potential pitfall in Medicare billing: modifer misuse

David Twiddy
June 10, 2014

Over the past two weeks, we have discussed how to avoid common Medicare billing errors recently identified by the Centers for Medicare & Medicaid Services (CMS). This week, we’ll focus on the pitfalls associated with a commonly used billing modifier.

There are times when family physicians do multiple, separate procedures on the same patient at the same session or on the same day, for which separate payment may be allowed. Medicare rules state that the second and any subsequent procedures are subject to reduced payment in this situation. Physicians are to identify such services by appending modifier 51 (multiple procedures) to the codes for the second and subsequent procedures. Medicare, in turn, reduces the payment allowance by 50 percent for codes with modifier 51 attached.

Unfortunately, the CMS has identified situations in which physicians are appending modifier 51 to a procedure code even when that procedure is the only one provided to the patient on that date. In those situations, the physicians are generating inappropriate underpayments of up to 50 percent and shooting themselves in the foot financially. The easy answer is to NOT append modifier 51 to any code in the surgery section of Current Procedural Terminology (codes 10021 to 69990) if that is the only code from that section provided to the patient on that date.

For further resources, CMS advises that you read section 40.6 of chapter 12 and section 30 of chapter 23 of the Medicare Claims Processing Manual. Next week, we’ll wrap up this series of posts by looking at the pitfalls associated with billing office visits for hospital inpatients.

– Kent Moore, Senior Strategist for Physician Payment for the American Academy of Family Physicians

Posted on Jun 10, 2014 by David Twiddy

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