Introduction
Claim denials can significantly disrupt the operations of gastroenterology practices, affecting their financial stability and overall patient care. Given the high volume of procedures such as colonoscopies, endoscopic ultrasounds, and therapeutic interventions, gastroenterologists are at a heightened risk for denied claims. Denial rates in gastroenterology typically range between 10-15%, leading to substantial revenue losses that can amount to hundreds of thousands of dollars annually.
In this post, we’ll discuss the top denial reasons specific to gastroenterology, the causes behind these denials, and how to prevent them. By improving billing practices, staying current on payer policies, and keeping accurate documentation, gastroenterology practices can reduce claim rejections, lower administrative costs, and get properly reimbursed for the care they provide.
Common Denial Codes in Oncology
| Denial Code | Description |
|---|---|
CO 50 | Not Medically Necessary Service |
CO 197 | Pre-certification/authorization required |
CO 16 | Missing/incomplete information |
CO 96 | Non-covered service |
CO 234 | Procedure code/modifier inconsistent |
CO 97 | Service included in global period |
CO B7 | Provider not eligible/credentialed |
CO 109 | Not covered by this payer/contractor |
CO 204 | Not covered under patient’s benefit plan |
CO 151 | Payment adjusted because the payer deems the information submitted does not support this level of service |
Detailed Analysis of Top 10 Denials
1. Denial Code: CO 50
Description: Medical Necessity Denials
Medical necessity denials occur when payers determine that a gastroenterology service or procedure doesn’t meet the required clinical guidelines. In gastroenterology, these denials often impact procedures like colonoscopies, especially when documentation fails to clearly justify the need based on symptoms, risk factors, or screening recommendations. For example, a colonoscopy may be denied if it’s performed earlier than the recommended screening intervals without documenting symptoms or risk factors that warrant the early procedure.
Similarly, repeat endoscopic procedures performed within a short period may be denied if there’s insufficient evidence showing ongoing symptoms or a change in the patient’s condition. These denials are especially common with surveillance colonoscopies for patients with a history of polyps or inflammatory bowel disease, where accurate documentation of previous findings and adherence to recommended surveillance intervals are vital yet often lacking.
Prevention:
- Create clear guidelines for physicians on documenting symptoms, risk factors, and clinical indications for endoscopic procedures
- Implement screening tools to verify procedure intervals align with specialty guidelines (ACG, ASGE, AGA)
- Document family history and personal risk factors thoroughly when recommending early screening
- For surveillance colonoscopies, clearly document previous findings, pathology results, and recommended follow-up intervals
- Create specific documentation templates for repeat procedures that clearly address persistence of symptoms or new clinical findings
2. Denial Code: CO 197
Description: Pre-certification/Authorization Issues
Authorization denials happen when pre-approval wasn’t obtained before performing a gastroenterology procedure that requires it. In GI practices, this often applies to advanced procedures like endoscopic ultrasound (EUS), ERCP, capsule endoscopy, and motility testing. These denials can be costly, as they typically result in full denial of payment for high-priced services.
Securing prior authorization can be particularly difficult in urgent cases—such as acute GI bleeding or biliary obstruction—where immediate intervention is needed and waiting for approval may affect patient care. Additionally, payers often have specific and inconsistent requirements for authorizing these procedures, making the process even more complex for gastroenterology teams.
Prevention:
- Implement a robust tracking system for gastroenterology procedure authorizations
- Train scheduling staff on specific authorization requirements for advanced GI procedures
- Establish protocols for urgent/emergent situations requiring retrospective authorization
- Document all authorization numbers, dates, and specifics in both clinical and billing systems
- Verify authorization status before performing GI procedures
3. Denial Code: CO 16
Description: Missing/Incomplete Information
These denials arise when claims are submitted with errors or missing details. In gastroenterology, they often stem from incorrect or incomplete diagnosis codes especially for complex conditions like inflammatory bowel disease, liver disorders, or functional GI issues. Other common problems include missing modifiers on endoscopic procedures or incomplete documentation of what was done during the procedure.
Because GI coding involves multiple layers such as identifying the specific location, findings, and actions taken any gaps in documentation can easily lead to a denial. The technical nature of endoscopic coding makes accuracy critical but also increases the chance of small mistakes leading to rejected claims.
Prevention:
- Verify all required documentation is present before claim submission
- Develop procedure-specific documentation templates for common GI services
- Create standardized documentation templates for endoscopic reports that capture all required elements
- Implement quality control reviews before claim submission
- Conduct regular audits to identify patterns of incomplete information
4. Denial Code: CO 96
Description: Non-covered Service
Non-covered service denials occur when a gastroenterology procedure is not included in a patient’s insurance benefits. These denials often involve newer or specialized services like fecal microbiota transplants for recurrent C. difficile, advanced motility studies, certain genetic tests, or experimental treatments for conditions like inflammatory bowel disease.
Unlike medical necessity denials, these services are excluded from coverage even if they’re clinically appropriate. This can leave patients responsible for the full cost, which can be significant, especially for high-priced or less commonly performed GI procedures. These denials present both financial and communication challenges for practices and patients alike.
Prevention:
- Verify specific coverage for planned GI treatments during insurance verification
- Create a database of commonly non-covered gastroenterological services by payer
- Implement advance beneficiary notice (ABN) protocols for Medicare patients
- Develop similar financial responsibility forms for commercial payers
- Train scheduling staff to identify potentially non-covered GI services
5. Denial Code: CO 234
Description: Procedure Code/Modifier Inconsistency
These denials happen when procedure codes and modifiers are used incorrectly or don’t align with payer guidelines. In gastroenterology, this often affects advanced endoscopic procedures like polypectomies, endoscopic mucosal resection, or cases where multiple procedures are done during the same session.
Common issues include using the wrong modifier when billing for both diagnostic and therapeutic parts of a procedure, or not updating the code when a screening colonoscopy becomes diagnostic after a polyp is found. Because GI procedures often involve multiple steps and code combinations, even small coding errors can lead to denials, making this a frequent issue for gastroenterology practices.
Prevention:
- Implement claim scrubbing tools that verify proper modifier-procedure combinations
- Create procedure-specific coding templates for complex GI interventions
- Conduct regular audits of modifier usage, especially for high-dollar procedures
- Stay updated on payer-specific modifier requirements for gastroenterology
- Review denied claims to identify problematic modifier patterns
6. Denial Code: CO 97
Description: Service Included in Global Period
Global period denials occur when services performed during a global period are incorrectly billed separately. In gastroenterology, this often affects follow-up visits or additional procedures done within the global period of a prior GI surgery or intervention. Many GI procedures have global periods (usually 0, 10, or 90 days), meaning post-procedure care is considered part of the original payment.
Claims for services during this time related to the original procedure will be denied unless clearly documented and coded as separate from the global package. These denials are especially challenging in gastroenterology, where patients with complex GI conditions may need frequent follow-ups or multiple procedures in a short span of time.
Prevention:
- Create procedure-specific guidelines for global period management
- Train providers on documentation requirements for services outside the global package
- Properly use modifiers (-24, -25, -78, -79) to indicate unrelated or distinct services
- Implement tracking systems for patients in global periods
- Develop clear guidelines for coding post-procedure complications versus unrelated conditions
7. Denial Code: CO B7
Description: Provider Not Eligible/Credentialed
These denials occur when claims are submitted for a provider who is not properly enrolled, credentialed, or authorized under the patient’s insurance plan. In gastroenterology, this often affects new physicians joining a practice, advanced practice providers performing certain GI procedures, or gastroenterologists working at facilities where they may not be fully credentialed.
These denials are especially challenging when urgent gastroenterological care is needed and the nearest available provider is out of network. Additionally, managing credentialing across multiple facilities (e.g., ambulatory surgery centers, hospitals, office-based labs) further complicates the process and can lead to denials if not properly updated and maintained.
Prevention:
- Implement software that prevents claim submission for non-credentialed providers
- Create regular credentialing status reports for all gastroenterologists across all facilities
- Train scheduling staff to match patients with appropriately credentialed providers
- Start recredentialing processes at least 90 days before expiration
- Consider using a credentialing verification organization (CVO) to streamline the process
8. Denial Code: C0 109
Description: Not Covered by This Payer/Contractor
These denials occur when services are provided by an out-of-network gastroenterology provider. With the rise of narrow networks and tiered benefit plans, patients may not realize that their gastroenterologist or the facility performing procedures (such as ambulatory surgery centers or hospital outpatient departments) is out-of-network until after care is delivered.
These denials are especially difficult for gastroenterology practices, as they often lead to substantial patient financial responsibility for expensive procedures. In emergency situations, such as GI bleeding or acute pancreatitis, patients may require immediate care from the nearest available gastroenterologist, regardless of network status, which adds to the complexity of these denials.
Prevention:
- Implement real-time eligibility verification technology
- Train front desk staff to verify in-network status for both routine and urgent appointments
- Develop clear financial policies for out-of-network patients
- Create patient-friendly explanations of potential financial responsibility
- Consider contracts with major payers in your region to maximize network participation
9. Denial Code: C0 204
Description: Not Covered Under Patient’s Benefit Plan
These denials occur when a specific gastroenterological service is not covered under a patient’s particular insurance plan, even if the same service might be covered under other plans from the same insurer. In gastroenterology, this often impacts bariatric procedures, advanced diagnostic tests like wireless motility capsules, specialized treatments for inflammatory bowel disease, or certain endoscopic procedures that some payers may consider experimental.
These denials can be especially frustrating due to the variability in coverage across different plans offered by the same insurer, making it challenging to determine in advance which services will be covered for individual patients.
Prevention:
- Verify specific plan coverage for planned GI procedures during insurance verification
- Create a database of commonly excluded gastroenterological services by specific plans
- Develop plan-specific verification protocols for high-risk procedures
- Implement advance beneficiary notice (ABN) protocols for Medicare patients
- Create similar financial responsibility forms for commercial plans
10. Denial Code: CO 151
Description: Level of Service Not Supported
These denials occur when the documentation fails to support the level or complexity of the gastroenterological service billed. In gastroenterology, this commonly affects evaluation and management services provided with endoscopic procedures, complex consultations for patients with multiple GI conditions, or situations where services typically performed by specialists are provided by non-specialists.
Payers may deny claims if the documentation does not clearly demonstrate the medical decision-making complexity, time spent, or the specialized expertise required for the billed service. Given the complexity of gastroenterology care, which often involves multiple organ systems and chronic disease management, it is crucial to ensure that documentation fully reflects the work involved, though this can be challenging.
Prevention:
- Provide education on the specific elements required to support each service level
- Create quick-reference guides showing documentation requirements by service level
- Develop standardized documentation language for common gastroenterological scenarios
- Implement peer review processes for complex GI cases
- Consider specialized coding education focusing on gastroenterology service levels
Conclusion
To tackle claim denials effectively in gastroenterology practices, it’s essential to focus on key areas like accurate documentation and clear communication between clinical and billing teams. The complexities of GI procedures and coding can lead to frequent denials, especially when details are missed or incorrectly reported. A proactive approach involves regularly reviewing denied claims to identify patterns, which helps pinpoint where improvements can be made.
Practices should also invest in training for both clinical and administrative staff, so they are aware of the latest payer guidelines and requirements. Continuously refining workflows and maintaining updated coding practices will ensure better reimbursement outcomes. By taking a more organized approach to denial management, gastroenterology practices can reduce administrative challenges, improve their financial health, and provide timely care to patients without unnecessary barriers. This will not only improve practice operations but also reduce patient stress over denied claims.