How to Determine Date of Service for Part B Billing of Outpatient Lab Tests

Date of service rules affect whether outpatient lab tests are part of the Hospital Outpatient Prospective Payment System (HOPPS) bundled payment or can be billed separately under Part B. Last month, CMS issued guidance clarifying how providers should apply the new rules on their CMS-1500 and/or X12 837 Professional Claim forms. Here’s what you need to know if you bill outpatient lab tests under Part B.

General Date of Service Rule
The date of service for clinical lab services is generally the date the specimen is collected. If the specimen is collected over a period that spans two calendar dates, the date of service is the date the collection ended. However, as the guidance notes, there are three exceptions:

Exception 1: Date of Service for Tests on Stored Specimen

The date of service depends on how long the specimen was stored:

If specimen is stored ≤ 30 calendar days from date it was collected: The date of service of the test/service is the date the test/service was performed, provided that:

• The specimen was collected while the patient was undergoing a hospital surgical procedure;
• It would be medically inappropriate to have collected the sample other than during the hospital procedure for which the patient was admitted;
• The results of the test/service don’t guide treatment provided during the hospital stay; and
• The test/service was reasonable and necessary for the treatment of an illness.

If specimen is stored more than 30 calendar days before testing: The specimen is considered to have been archived and the date of service of the test/service is the date the specimen was obtained from storage.

Exception 2: Date of Service for Chemotherapy Sensitivity Tests on Live Tissue

The date of service of the test/service is the date the test/service was performed, provided that:

• The decision as to the specific chemotherapy agent to test is made at least 14 days after discharge;
• The specimen was collected while the patient was undergoing a hospital surgical procedure;
• It would be medically inappropriate to have collected the sample other than during the hospital procedure for which the patient was admitted;
• The results of the test/service don’t guide treatment provided during the hospital stay; and
• The test/service was reasonable and medically necessary for treatment of an illness.

Exception 3: Date of Service for Advanced Diagnostic Laboratory Tests (ADLTs) and Molecular Pathology Tests

The date of testing for a molecular pathology test or a test designated by CMS as an ADLT under paragraph (1) of the definition of advanced diagnostic laboratory test in 42 CFR 414.502, is the date the test was performed, provided that:

• The test was performed following a hospital outpatient’s discharge from the hospital outpatient department;
• The specimen was collected from a hospital outpatient during an encounter;
• It was medically appropriate to collect the sample from the hospital outpatient during the hospital outpatient encounter;
• The results of the test don’t guide treatment provided during the hospital outpatient encounter; and
• The test was reasonable and necessary for the treatment of an illness.