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Correcting The Top Five Common Mistakes In Coding

A seemingly minor mistake in coding can lead to claim denials and reduced reimbursement. This author takes a closer look at common coding pitfalls, including errors with modifiers, downcoding and LCDs, and how to reduce repeat coding errors.

It is no shock to anyone that billing for our podiatric services is becoming more and more complicated. Regardless of how qualified the physician is, practices can struggle if the revenue stream is not adequate.

Keeping up with changes in billing is complicated by the reality that we are all trying to do more with less staff. Additional time spent complying with insurance company and government mandates adds more stress to the office workflow, increasing the probability of making billing mistakes. Although many of these mistakes are simple ones, they can significantly impact your collections.

Below are five areas where common mistakes can impact your bottom line.

Avoiding Pitfalls With Modifiers

When billing, a CPT code matches up to an ICD-10 code. At face value, this would seem to be a very straightforward process but there are always variations/exceptions to everything. Sometimes, there are related services that the physician is performing, global periods to contend with, etc. Modifiers will clarify extenuating circumstances, which should allow for payment when they otherwise may not.

That said, the improper use of modifiers can be the cause of claim denials just as not using a modifier can be. When using modifiers, make sure you clearly understand what the modifier entails.

If the insurance company denies a claim and you rebill it by simply choosing another modifier and hoping that is the correct one, this will usually end up creating additional problems. Remember that insurance companies may have a time limit as to how long you can file an appeal. If you continually rebill incorrectly, then by the time you send in the claims and subsequently get denied again, you may run yourself out of the appeal window. The appeal window generally starts when you submit the initial claim. Medicare explanation of medical benefits (EOMBs) will indicate whether you can appeal a claim rather than rebilling, depending on the error.

There are three specific evaluation and management (E/M) modifiers. These are the -24, -25 and -57 modifiers. Only use these modifiers with E/M services. If you append them to any other service such as a diagnostic study or procedure, the carrier will automatically deny your claim.

The -25 modifier is the most confusing and most audited modifier. Use this modifier when the E/M service is “significant and separately identifiable” from the procedure you are performing on the same day. Those terms are vague and liable to subjective interpretation on the part of the insurance carrier. Your best defense in an audit and the basis for appeal is rock solid documentation of the patient history, the examination you performed and the resultant decision making. It is not proper to bill an E/M service every time you perform a procedure as some sort of a baseline office fee. Excessive use of this modifier will flag you for an audit.

Other modifiers that can cause confusion are whether to use a RT or LT modifier versus the -50 modifier when rendering bilateral services. Incorrectly selecting the wrong modifier will result in the claim being denied. Unfortunately, there is no rhyme or reason as to when to use the RT/LT modifiers versus the -50 modifier. The best course of action is to check the Correct Coding Initiative edits, which are available at the Centers for Medicare and Medicaid Services (CMS) website or in a podiatry-focused resource such as the American Podiatric Medical Association (APMA) Coding Resource Center. This will tell you whether that specific CPT code requires a single line billed with the -50 modifier or if you need to bill two separate lines with the RT and LT modifier.

As a rule, do not use the -51 modifier especially for Medicare claims. This seems to kick out claims automatically. The -51 modifier simply states that multiple procedures are happening at the same visit. Most of the insurance company software will already take that into account when processing your claim and reduce payment on the secondary billing lines.

Use T codes to differentiate billing for separate digits. T codes are digital codes and are for services distal to the metatarsophalangeal joint. Accordingly, do not use a TA modifier when performing a bunion surgery. Use T codes to separate surgery performed on multiple toes. If you only operate on a single toe, then there is no need to use a T modifier.

How To Unbundle Services Properly

Unbundling is often a negative term, implying that a base procedure is improperly broken down into its component parts. It is often the case that billing each of the component parts results in a much higher payment than billing the overall comprehensive code. A basic tenet in billing is that if there is a code that incorporates the various components of a procedure into one universal code, that is the code to use regardless of reimbursement amounts. Unbundling simply to obtain a higher reimbursement can be considered abusive if not fraudulent billing.

That said, many services are legitimately unbundled. Codes are simply codes. They do not necessarily reflect what the physician did and where. Two codes may very well be bundled together but are payable separately when one performs them at two different anatomical sites. An example would be billing an arthroplasty code and a bunion code. Bundle these together if you are not using any modifiers. Using the appropriate modifier will allow a bunion procedure to get properly paid as well as the arthroplasty procedure when you perform these procedures on a lesser digit. Another example is billing for multiple individual “single” procedures when there is a code that describes the same procedure but is listed as “multiple.”

Rectifying Downcoding Mistakes

Downcoding is another common mistake. This is the opposite of upcoding, which implies billing for a higher level of service or different services than is otherwise appropriate. Downcoding does not serve any purpose.

The thought is that if you downcode and bill a lower level code (generally an E/M service), you will “fly under the radar,” thereby minimizing the odds of being audited by insurance companies. Many audits are based strictly on statistics. Providers who tend to be two standard deviations above or below the mean are obviously suspect. An insurance company could very well be concerned that by downcoding, although you may not be charging the insurance company as much money, some of that billing can still be fraudulent.

If you are downcoding, you may also be cheating yourself out of legitimate money. There seem to be more and more cutbacks with changing relative value units (RVUs), sequestration, and not participating in the Merit-Based Incentive Payment System (MIPS)/Medicare Access and the CHIP Reauthorization Act (MACRA) program in which there are penalties, all of which continue to erode your reimbursements. Downcoding simply adds more loss to your revenue stream. Bill for what you do and have your chart note ready to back up your billing

Learning from EMOBs In Order To Appeal And Reduce Claim Denials

We are all very busy in our offices. Trying to stay on top of changes in billing protocols is very difficult. Often when the insurance company denies claims and the amount of money involved is small, it may not seem worth the time, effort and cost to appeal. However, there is a ton of information in the EOMB that will not only help you get paid for your services but more importantly also educate you as to billing protocols you may be missing.

A denial states that the insurance carrier believes that you billed inappropriately. This is not always the case. You may have billed properly and the carrier may have simply processed your claim incorrectly. Claims processing is computerized and glitches do happen. That said, you may have billed inappropriately.

Rather than get frustrated and upset at the denied claim, carefully read the explanation of benefits. That will give you insight as to why the carrier denied the claim and will give you the basis for your appeal. Unfortunately, many insurance companies have a limited number of templated denial rationales that they select from when denying a claim so it may not be one hundred percent accurate or clear. Yet the claim may say you billed an inappropriate modifier, which gives you a clue that you may need to refresh your knowledge of that modifier and how to use it properly. The carrier may have bundled your claim, which again gives you information that other modifiers may be appropriate to legitimately unbundle your claim.

Writing an appeal letter based on the incorrect denial rationale will not get that claim paid. You need to address the carrier’s specific question. The denial may not be a medical necessity issue at all. Rather, it may simply be a technical error that is easily fixed. In this instance, arguing the medical necessity of the service rendered and submitting supporting journal articles, etc., will not help your appeal in any way.

Local Coverage Determination Policies: What You Should Know

Local coverage determination (LCD) policy and similar insurance carriers policies are in place either because the carrier believes there is sufficient confusion or because of abusive billing of a certain CPT code. This serves as a program safeguard measure but can also serve as a mechanism to help educate the provider and the billing staff.

An LCD will clearly list which ICD-10 codes are payable for a specific CPT code. Even with the recent switch to ICD-10 and the significantly increased number of codes available, there is no ICD-10 code for every possible scenario. Many ICD-10 codes overlap and you may sometimes have to choose between two similar codes. However, only one of those codes may be on the LCD and you need to know the proper code to use. Often, the Medicare EOMB denial will make a reference to an LCD, which is your opportunity to review that LCD as it may have been updated. Most insurance companies have their policies listed on the website so you can review that as well.

The LCD also gives you information that may tell you how frequent services such as routine foot care are allowed or how many times a service is allowed within a given period of time. An LCD may also give you information as to other ICD-10 codes that may be required as a secondary code for payment. Certain products, such as wound care products, are only indicated for certain types of wounds. The LCD may offer information for that as well.

The LCD may also tell you not to use the wound care product until after rendering a certain amount of conservative care or using other parameters. All these LCDs offer billing information that allows you to bill properly and get paid for your services. With wound care products and other products, there is a direct cost to the practice versus just writing off your time. The manufacturer of the product still wants to be paid regardless of whether you get reimbursed or not.

In Conclusion

Mistakes are going to happen when billing claims. Some may be just random mistakes due to an inadvertent key stroke, being distracted in the office, not feeling well, etc. However, you should address and correct repeated errors.
If it is not worth the time and effort to correct that one specific claim, you can still take steps to make sure you do not repeat that mistake in the future. Little $20 to $30 write-offs may not seem like much but they do add up over time.

Turn a negative denial experience into a positive educational opportunity for your practice. Berating an employee does not help your practice financially nor does it improve the office environment. Educate and support your staff. While you are at it, sit in on some billing seminars/webinars and read educational materials. Filling out the “superbill” properly will also help your staff bill correctly.

Dr. Poggio is a California Podiatric Medicine Association Liaison to Palmetto GBA J1 MAC and a medical consultant to several national health insurance and review organizations. He is a member of the American College of Podiatric Medical Reviewers and is board-certified by the American Board of Podiatric Medicine and the American Board of Podiatric Orthopedics and Primary Podiatric Medicine.

For further reading, see “Imminent ICD-10-CM Changes You Need To Know,” the September 2018 DPM Blog by Jeffrey Lehrman, DPM at

By Anthony Poggio, DPM
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