Welcome to The Coding Corner, a space where doctors who are already excellent at doctoring can dig into the finer details of coding, documentation, compliance, and the occasional mystery that is the AMA Evaluation and Management (E/M) grid.
This month, Tonya Reynoldson, OD, and Sarah Haney discuss how the chief complaint affects billing documentation.
Tonya: Sarah, let's start with what sounds like a simple question: Why is the chief complaint so important from a coding and auditing standpoint?
Sarah: The chief complaint (CC) is the patient's reason for the encounter. CMS defines it as a short statement that describes the symptom, problem, condition, diagnosis, or reason for the encounter and notes that it is usually stated in the patient's own words.1
I like to think of the CC as the opening sentence of the story. It tells me why the patient walked through the door that day. The assessment and plan tell me where the story ended, but I need to understand how we got there.
From an auditor’s perspective, that becomes especially important when evaluating medical necessity. For every service billed, the record should show the specific sign, symptom, or patient complaint that makes the service reasonable and necessary.2 The CC may be short, but it carries a lot of weight.
Tonya: Let's say the patient schedules a comprehensive vision exam because they want new glasses, but the doctor discovers a medical condition during the examination. Does discovering pathology automatically change the nature of that encounter from routine to medical?
Sarah: No, and this is probably one of the most important concepts in this discussion.
The ending doesn't rewrite the beginning. CMS guidance specifically addresses this concept for eye examinations: “Coverage depends on the purpose of the examination rather than the ultimate diagnosis.”1 CMS explains that when a patient presents without a specific complaint for an eye examination, discovering pathology during that examination does not, by itself, make the original examination covered as a medical service.
That doesn't mean the newly discovered condition isn't important. It may absolutely require additional evaluation, testing, treatment, or a future medical encounter. But we shouldn't retrospectively change why the patient originally presented because we found something nonurgent.
Tonya: Can the CC change during an encounter? For example, a patient arrives for a routine vision examination but tells the doctor they have recently developed flashes and floaters. How should that be documented?
Sarah: Patients don't always tell the technician everything they eventually tell the doctor. Maybe they forgot. Maybe the doctor asked the question differently. We've all met the patient who tells the technician, “No changes!” and then gives the doctor an entirely new plotline 5 minutes later.
It is recommended to update the CC and relevant history when a complaint is voiced to the doctor that wasn't initially provided to the technician.3 If the doctor learns about new flashes and floaters, put that information in the record. Update or clarify the CC and history of present illness to accurately reflect the conversation that occurred and the clinical evaluation that followed. Don’t let a documentation gap negate a pertinent clinical conversation. If it isn’t captured in the record, the information needed to support medical necessity may be lost.
Tonya: How should the CC be documented for a scheduled medical follow-up? For example, with a glaucoma follow-up, does the patient need to report a new symptom for the encounter to be medically necessary? I think this is a question technicians and doctors struggle can with.
Sarah: No. Medical necessity does not require the patient to develop a brand-new symptom every time they return.A patient may be returning because the doctor is monitoring or managing a known condition. The CC can reflect that reason.
This is also where asking a few simple questions can make a big difference. Instead of stopping at “glaucoma follow-up,” ask: “How has your vision been since your last visit? Any changes? Are you using your drops as prescribed?Any problems or side effects with them?” The answers help document the patient’s current status and add additional context.
For example: “Patient returns for 6-month glaucoma follow-up as directed; reports vision stable, compliance with drops, and no new ocular complaints.”
That's much more informative than simply “follow-up.” It tells me what is being followed, why the patient is there, and the patient's current status. A stable patient can still require medically necessary care.
Tonya: Let's talk about technology. If a diagnostic test is performed during the visit, should the CC and history help explain why the doctor ultimately ordered that test?
Sarah: Yes, but I want to be careful here: The CC doesn't have to independently justify every diagnostic test.
Think of it as the beginning of the medical-necessity trail. The CC and history establish the patient's problem or reason for care. Examination findings, known diagnoses, prior testing, clinical changes, and the physician's assessment may then establish why a particular diagnostic test was reasonable and necessary.
Tonya: From an auditor's perspective, what are some CC red flags? Are there patterns you commonly see that make you look more closely at a chart?
Sarah: Definitely. A few that make me slow down:
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“Comprehensive eye exam,” “annual exam,” or “routine exam” paired with a medical office visit claim
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“Follow-up” with no indication of what is being followed
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The exact same CC copied across multiple visits
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A CC that doesn't align with the primary diagnosis
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Extensive diagnostic testing with little documentation explaining the clinical reason for it
None of those automatically proves something was coded incorrectly. They simply tell me I should keep reading.
Final takeaway: Document why the patient is in your chair today in their own words when possible, not what was on the schedule, not which insurance you hope will pay, not simply what diagnosis you discovered at the end of the examination. Why is this patient here today? The CC may be one of the shortest sentences in the chart, but from an auditor's perspective, and as it relates to eye care, it can be one of the most important.
So, does the CC really matter? We’ll let you answer that one. Until next month!
References
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Centers for Medicare & Medicaid Services. Evaluation and management services. Medicare Learning Network, MLN006764. May 2026. Accessed September 21, 2026. https://www.cms.gov/files/document/mln006764-evaluation-management-services.pdf
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Centers for Medicare & Medicaid Services. Medicare claims processing manual: coverage of services rendered by an ophthalmologist. Transmittal 1802. Accessed August 28, 2026. https://www.cms.gov/regulations-and-guidance/guidance/transmittals/downloads/r1802b3.pdf
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American Academy of Ophthalmology. Is the chief complaint important? Accessed August 28, 2026. www.aao.org/practice-management/news-detail/is-chief-complaint-important
