By Tiffany Mays, Performance Management Analyst
Like so many other highly trained specialists, gastroenterologists are facing shrinking reimbursements despite growing demand for their services. According to Becker’s ASC Review, gastroenterology is one of 13 specialties seeing reimbursement rates decline, even as volumes per beneficiary continue to climb. At the same time, a study in the American Journal of Gastroenterology found that reimbursements for colonoscopies and biopsies have dropped by 38% over the past 15 years.
With pressure mounting, the margin for error in billing and coding is razor thin. While GI billing is full of nuanced rules and complexities, the most important step is mastering the basics – authorizations, documentation, and core procedures. These fundamentals serve as the foundation of the entire revenue cycle, and when done right, they safeguard long-term financial stability.
Below I examine the key areas that form the backbone of GI billing and are critical to securing full reimbursement.
The role of prior authorizations
Prior authorization (PA) requirements are one of the top pain points for gastroenterology practices. Whether it’s a colonoscopy with polypectomy, an EGD, or a capsule endoscopy, payers often require prior approval before services can be rendered. Missing or incomplete authorizations almost always result in denials or delayed payments.
Best practices for managing PAs include:
- Verify authorization requirements for every procedure and every payer.
- Document authorization numbers clearly in the medical record and claim.
- Establish workflows for renewals or resubmissions when authorizations expire.
Managing prior authorizations effectively takes time and coordination, that’s why many groups turn to an experienced gastroenterology billing partner. The right partner can streamline PA management, ensure rapid eligibility verification, flag missing information before claims go out, and ultimately reduce costly write-offs.
Documentation: The foundation of clean claims
Accurate, detailed documentation is the backbone of successful gastroenterology billing. Each entry must support medical necessity and capture the specifics of the procedure performed. For example, documenting whether a colonoscopy was performed for screening versus diagnostic purposes directly impacts coding and reimbursement.
There are several key elements that providers should consistently capture in their documentation:
- Screening vs. diagnostic colonoscopy: There must be documentation regarding whether a procedure is a screening colonoscopy and covered under preventive care, versus if a colonoscopy is diagnostic. If a screening procedure identifies polyps and a polypectomy is performed, the coding shifts. That distinction must be documented to avoid denials and compliance risk.
- Level of detail: Documentation notes should capture location, number, and size of polyps, biopsy sites, and any therapeutic interventions performed.
- Linking diagnosis to procedure: Every CPT procedure code must be supported by an appropriate ICD-10 diagnosis code in the medical record. Without this clear link, payers may deny the claim for lack of medical necessity.
Strong documentation is more than a compliance requirement – it is the key to securing timely and accurate reimbursement. By consistently capturing the right details and aligning diagnoses with procedures, gastroenterology practices can reduce denials, defend medical necessity, and maintain a healthier revenue cycle.
Core GI procedures and coding challenges
Endoscopies and colonoscopies are the lifeblood of every gastroenterology practice. Due to the high volume of these core procedures, it is paramount they are billed accurately and at the highest level possible to ensure strong and consistent financial results.
Even with high-volume, routine procedures, their coding is far from straightforward. Each core service has its own detailed guidelines, and the complexity compounds when modifiers are required for multiple procedures in the same session, when global versus professional billing rules apply, or when CMS issues frequent code updates.
Common coding pitfalls for core procedures include:
- Incorrect use of modifiers (e.g., 59 vs. XS for bundled services)
- Confusion between screening and diagnostic coding
- Failure to capture add-on codes for procedures like biopsy or control of bleeding
Because core GI procedures are performed in such high volumes, even small coding errors can have a significant financial impact. Establishing clear protocols, keeping providers and staff up to date on code changes, and regularly auditing claims can help practices avoid costly mistakes and preserve revenue integrity.
Know your payer mix
Understanding who your payers are, and how they behave, is just as critical as proper coding. Commercial payers, Medicare, and Medicaid all reimburse differently and impose their own rules for authorizations, bundling, and preventive services. For example, while Medicare may fully cover a screening colonoscopy, commercial plans often impose different cost-sharing rules.
Analyzing payer performance can highlight trends such as:
- Higher denial rates from specific payers
- Delayed payment patterns
- Lower reimbursement for high-volume procedures
When gastroenterology practices better understand their payers, they can prioritize appeals, renegotiate contracts, and strengthen their revenue cycle. This is one reason many gastroenterology physician groups turn to high-achieving RCM partners who can bring more visibility and benchmarking into payer behavior.
Understand the reasons behind denials
Denials are one of the clearest signals of revenue leakage in gastroenterology billing. While they can’t be eliminated entirely, they can – and should – be analyzed, categorized, and reduced. Denials don’t just delay or lead to lost reimbursement, they also result in significant administrative burdens and cost the healthcare industry billions per year.
For GI physician groups, some of the most common reasons for denials, include:
- Missing or invalid authorizations
- Documentation not supporting medical necessity
- Incorrect modifiers or coding
- Duplicate claims or bundling errors
- Patient eligibility issues
Denials offer valuable insight into where breakdowns occur in the revenue cycle. By tracking patterns, addressing root causes, and building denial prevention into everyday workflows, gastroenterology practices can move from a reactive stance to a proactive approach – protecting revenue while improving efficiency.
Key takeaways
For gastroenterology physician groups, getting the basics right – authorizations, documentation, and core procedure coding – makes the difference between sustainable revenue and increasing financial strain. When you add in the complexities of payer-specific rules and declining reimbursement, it’s easy to understand why so many practices turn to experienced billing partners. Once physician groups have the right systems and expertise in place, they can devote their focus to patient care, knowing their bottom line is in good hands.
Health Prime can optimize your gastroenterology group’s revenue cycle. To learn more, please send us an email or visit us at hpiinc.com/gastroenterology.
