In this Article
By: Kendall Upton
Professional insights: Amy Jenkins
Medical coders play a critical role in the healthcare revenue cycle by translating physicians’ notes, procedures and treatments into standardized codes that insurance companies and payers can use for billing and reimbursement. Their accuracy ensures that providers receive compensation for the care they deliver while also maintaining compliance with regulations and avoiding costly errors.
One of the more complex tools coders must master in this process is the use of modifiers. These codes add important details to clarify how, why and under what circumstances a service was provided. When used correctly, they ensure that claims are precise and compliant. When used incorrectly, they can trigger denials, audits or even accusations of fraud. Understanding modifiers is key for coders aiming to uphold accuracy and protect a practice’s financial stability.
What are medical coding modifiers?
Modifiers are two-character codes (numbers or letters) that medical coders can add to CPT or HCPCS Level II codes. They provide additional context about a medical procedure and can indicate anything from multiple procedures performed during a single encounter to unusual circumstances that affect billing.
“Modifiers take the procedure that was performed and tell a story about why it’s different,” said Amy Jenkins, Clinical Assistant Professor in Health Systems and Population Health at the University of Washington School of Public Health. “It adds context to the circumstances that happened for that particular patient that would have been exceptional.”
How medical coders use modifiers
Medical coders append modifiers to CPT or HCPCS Level II codes when they need to tell the story of a procedure or service because it occurred under abnormal circumstances.
“For example, oftentimes visits that happen postoperatively are included in the procedure. Medicare values the entire procedure—the preop and postoperative care and all of the work that happens for the procedure—into one payment, a global surgery payment,” Jenkins said.
As an example, Jenkins posed a scenario where perhaps she fractured her leg. She goes in for surgery to have pins placed and then comes back to the hospital in the postoperative period so they can check on the leg’s progress. Only this time, somehow, she’s also broken her other leg.
“Under normal circumstances, that visit would be considered bundled into the procedure, but now it’s for a separate reason. So now we can add a modifier 24 that says, ‘Hey, by the way, this is a completely separate reason that this patient’s being seen. It’s not related to that initial surgery at all.’”
Ordinarily, the insurance company only sees the procedure and the diagnosis on the claim—they’re not seeing the documentation and the additional circumstances around that claim. “So really [the modifier] is more of a flag that says, ‘Look at this differently, please.’ And it helps the claim bypass their editing software, because their editing software is designed to say, ‘Nope, we’re going to kick that out and reject it if it’s within this time period,’” Jenkins said.
Common modifiers
Take a look at some of these common CPT coding modifiers that cause confusion and what they mean. For more detailed information on all coding modifiers and their correct use, be sure to consult industry-approved sources from organizations like the AAPC (formerly known as the American Academy of Professional Coders), American Medical Association (AMA), Centers for Medicare & Medicaid Services (CMS) and more.
Modifier 25
Modifier 25 indicates that the patient received an evaluation and management (E/M) service on the same day as another E/M service or procedure.
For instance, let’s say a patient sees their cardiologist because they’re experiencing some chest pain when they exercise. If the provider determined that the patient should complete a cardiovascular stress test that same day after their in-office evaluation, the provider would need to use modifier 25 to bill for that additional test.
Modifier 26
Modifier 26 means that the provider interprets the results of a test that they didn’t personally perform. For example, perhaps a physician orders a test for their patient from an external lab. The lab’s pathologist gives the physician a report with their interpretation of those test results, and can therefore use modifier 26 on their bill.
Modifier 51
Modifier 51 indicates that the provider performed multiple procedures in the same encounter. This can include different procedures performed at the same session, one procedure performed multiple times at different anatomical sites or one procedure performed multiple times at the same site. Coders should not add modifier 51 onto E/M codes.
If a dermatologist removed multiple skin lesions from different areas of the patient’s body in the same visit, for instance, then modifier 51 becomes appropriate.
Modifier 59
Modifier 59 lets coders communicate that providers performed two distinct, non-E/M procedures or services on the same day, but these procedures were not related to each other and therefore should not be bundled together. Coders often use this modifier to indicate that the physician performed two distinct procedures on different parts of the body, but there are other uses as well. Like modifier 51, coders should not pair modifier 59 with E/M codes.
As an example, modifier 59 would be appropriate if a surgeon performs a biopsy on one area of an organ during the same surgery in which a tumor is removed from that same organ.
“While modifier 51 and 59 both apply to additional procedures performed on the same date of service as the primary procedure, modifier 51 differs from modifier 59 in that it applies to procedures that may be more commonly expected to be performed during the same session,” says the American Society of Anesthesiologists.
Common modifier mistakes
Modifiers add an additional layer of complexity to an insurance claim that can cause confusion, denials, payment delays and other issues. Regulators could flag coding errors which are frequent or severe enough as fraud.
Jenkins said that she thinks the biggest mistake people make with modifiers—both intentionally and unintentionally—is automating their use.
“Modifiers are designed to be an exception-based use. We have incredible tools available to us in our charge capture and EHR [electronic health record] systems, so we are able to bill things that aren’t always compliant,” Jenkins said. “For example, take urine drug screens. There’s one code for that, but there’s also the ability to separate out codes if they’re done in different circumstances. But if you are trying to bypass that with a modifier 59 or whatever modifier might be appropriate, and you’re automating that into your charge capture system, then that is the exact antithesis of what the use of the modifiers are designed for, which is an exception use. They say, ‘Hey, normally we know these are bundled. We know we normally get paid for these things together, but we’re asking for you to unbundle them in this particular case, because of X, Y and Z.’”
Why accurate coding matters
When errors occur in the billing cycle, it can cause a cascade of issues that affect providers, payers and patients alike.
“Proper use of modifiers is important both for accurate coding and because some modifiers affect reimbursement for the provider. Omitting modifiers or using the wrong modifiers may cause claim denials that lead to rework, payment delays and potential reimbursement loss,” the AAPC says.
Medical coders are introduced to modifiers in a medical billing and coding program, but their education shouldn’t stop there. By pursuing industry certifications, joining professional associations and simply reading up on the latest changes to the medical coding world, medical coders can learn to master modifiers and help keep healthcare operations running smoothly and efficiently for everyone.
