Accurate laboratory claim submission is crucial for timely reimbursement and compliance. This comprehensive guide provides essential information for billing laboratory services to both Medicare and commercial payers, with a special focus on UnitedHealthcare requirements and the critical role of the CMS-1500 form. Understanding these guidelines, including National Provider Identifier (NPI) requirements and specific coverage criteria, is key to avoiding claim rejections and denials.

General Requirements for Laboratory Claim Submission

Submitting a successful laboratory claim, primarily using the CMS-1500 form, requires meticulous attention to detail. All services must be medically necessary and clearly documented in the patient’s medical record. Adherence to payer-specific rules and federal regulations is paramount for accurate claims processing.

The Critical Role of the Referring Physician’s NPI

For virtually all laboratory claims, it is critically important to include the National Provider Identifier (NPI) of the referring or ordering physician. This requirement extends beyond specific payer policies like UnitedHealthcare and is fundamental for several reasons:

• Establishing Medical Necessity: The NPI links the laboratory service directly to the ordering provider’s medical justification for the test, ensuring the service meets medical necessity criteria.
• Compliance with Regulations: Many federal and state laws mandate that laboratory services are ordered by a licensed physician, and the NPI helps ensure compliance with these regulations.
• Payer Requirements: Payers utilize the referring physician’s NPI to verify the validity of the order and to facilitate benefit coordination if necessary.

Laboratory claims that do not include the identity of the referring physician, via their NPI, will invariably be rejected or denied, leading to payment delays and increased administrative burden.

Key Elements of a Complete CMS-1500 Claim for Lab Services

A “Complete Claim” for laboratory services on the CMS-1500 form must accurately include the following essential elements:

• Patient Demographics: Full name, address, date of birth, sex, and Medicare/insurance ID number.
• Insured Information: Policyholder details if different from the patient, including their NPI if they are also a provider.
• Rendering Provider Details: The laboratory’s NPI, name, and address.
• Referring Physician Details: The referring/ordering physician’s full name and NPI (typically in Box 17 and 17b of the CMS-1500 form).
• Date of Service (DOS): The exact date(s) the laboratory services were performed.
• CPT/HCPCS Codes: Accurate Current Procedural Terminology (CPT) or Healthcare Common Procedure Coding System (HCPCS) codes describing the specific lab tests performed.
• Modifiers: Appropriate modifiers (e.g., -26 for professional component, -TC for technical component, or other specific laboratory modifiers) as required by the payer.
• ICD-10 Diagnosis Codes: Precise International Classification of Diseases, Tenth Revision (ICD-10) diagnosis codes that clearly establish the medical necessity for each laboratory test. These codes must directly support the services billed.
• Units: The number of units for each procedure code, if applicable.

Medicare Coverage Guidelines for Laboratory Services

Medicare coverage for laboratory services is generally limited to tests that are medically reasonable and necessary for the diagnosis or treatment of illness or injury, or to improve the functioning of a malformed body part. This is often outlined in National Coverage Determinations (NCDs) and Local Coverage Determinations (LCDs) established by the Centers for Medicare & Medicaid Services (CMS). Providers should always consult the most current NCDs and LCDs for specific coverage criteria and limitations.

Glycated Hemoglobin/Glycated Protein (NCD 190.21)

Testing for glycated hemoglobin (HbA1c) and glycated protein (fructosamine) is generally considered medically necessary by Medicare for the management of diabetes mellitus. Key coverage specifics include:

• For controlled diabetic patients, Medicare coverage for HbA1c testing is typically limited to once every three months.
• For diabetic pregnant women, testing may be covered once a month.
• Glycated protein (fructosamine) testing may be indicated for patients with abnormalities of erythrocytes, such as hemolytic anemia, where HbA1c may be unreliable for monitoring glycemic control.

Refer to CMS NCD 190.21: Glycated Hemoglobin/Glycated Protein for comprehensive details.

Thyroid Testing (NCD 190.22)

Medicare covers various thyroid function tests (e.g., TSH, fT-4, T4, T3 uptake) when medically necessary to diagnose or monitor thyroid dysfunction. Specific guidelines include:

• For clinically stable patients with known thyroid conditions, testing may be covered up to two times a year.
• More frequent testing may be allowed when there is an altered therapy regimen or significant changes in symptoms warranting closer monitoring.

Refer to CMS NCD 190.22: Thyroid Testing for comprehensive details.

Lipid Testing (NCD 190.23)

Lipid testing is covered by Medicare when indicated for evaluating atherosclerotic cardiovascular disease, primary dyslipidemia, or other associated conditions. It is crucial to note the following:

• Routine screening and prophylactic testing for lipid disorders are generally NOT covered by Medicare. Coverage is typically tied to specific medical conditions or monitoring of existing therapy.
• For monitoring patients on anti-lipid therapy, testing may be covered annually.
• Up to six tests may be covered in the first year for initial therapy adjustments, followed by annual monitoring thereafter, for patients actively undergoing treatment.

Refer to CMS NCD 190.23: Lipid Testing for comprehensive details.

Carcinoembryonic Antigen (CEA) (NCD 190.26)

Carcinoembryonic Antigen (CEA) testing serves as a biochemical marker primarily for monitoring the recurrence or progression of colorectal carcinoma and other malignancies. Medicare coverage frequency limitations include:

• Generally, CEA testing is not covered more often than once per chemotherapy cycle for patients with metastatic solid tumors.
• For patients post-surgical treatment for colorectal carcinoma, testing is typically covered every two months for monitoring recurrence.

Refer to CMS NCD 190.26: Carcinoembryonic Antigen (CEA) for comprehensive details.

UnitedHealthcare-Specific Laboratory Claim Requirements

UnitedHealthcare (UHC) has specific policies that providers must adhere to when submitting claims for laboratory services. Many UHC benefit plan designs exclude from coverage outpatient diagnostic services that were not ordered by a participating physician. Furthermore, UHC benefit plans may handle diagnostic services differently when a portion of the service (e.g., blood draw) occurs in the physician’s office, but the analysis is performed by a laboratory provider. State laws also frequently require that most, if not all, laboratory services be ordered by a licensed physician.

NPI Requirement for Referring Physicians with UnitedHealthcare

Consistent with general billing best practices and often mandated by state law, UnitedHealthcare explicitly requires that all laboratory claims include the NPI number of the referring physician. Claims submitted without the referring physician’s identity will be rejected or denied by UnitedHealthcare. This requirement applies to claims for both anatomic and clinical laboratory services.

Understanding Participating vs. Non-Participating Laboratories

The requirement to include the referring physician’s NPI applies to claims received from both participating and non-participating laboratories, unless specifically exempted by applicable law. For laboratory services provided by physicians within their own offices, this specific NPI requirement for referring physicians typically does not apply. Providers should also refer to the Protocol on Use of Non-Participating Laboratory Services for UnitedHealthcare’s specific guidance on this matter.

Disclaimer: The information provided in this guide is for informational purposes only and is not intended as medical or legal advice. Billing and coding regulations, as well as payer-specific policies, are subject to frequent change. Providers are strongly advised to verify the most current payer-specific policies, National Coverage Determinations (NCDs), and Local Coverage Determinations (LCDs) with the respective payers (e.g., CMS, UnitedHealthcare) to ensure accurate and compliant claim submission.

Original content for UnitedHealthcare sections based on information from How to submit claim for Laboratory service (2011).