Medicare Compliance & Reimbursement

Tip: Look to HCPCS codes to get reimbursement.

If you’re reporting drug screening tests for Medicare beneficiaries, keep in mind that Medicare won’t accept CPT^® drug screen codes 80100, 80101, or 80104.

Turn to HCPCS Level II for Medicare

Instead, you’ll need to report one of the following codes if a physician orders a drug screen for a Medicare beneficiary:

• G0431 — Drug screen, qualitative; multiple drug classes by high complexity test method (e.g., immunoassay, enzyme assay), per patient encounter;
• G0434 — Drug screen, other than chromatographic; any number of drug classes, by CLIA waived test or moderate complexity test, per patient encounter.

You can see that CMS has established a two-tier drug-screen coding system that doesn’t align with the distinctions you’d make if you’re reporting CPT^® drug test codes.

Know CLIA Certification

The key to selecting the proper HCPCS Level II drug screening code is understanding how the Clinical Laboratory Improvement Amendments (CLIA) categorizes tests into three complexity groups, as follows:

• Waived tests;
• Tests of moderate complexity, including the subcategory of provider-performed microscopy (PPM) procedures;
• Tests of high complexity.

“You should choose between G0431 and G0434 based on the CLIA complexity classification of the specific lab test you’re using,” says Robin Miller Zweifel, MT (ASCP), a laboratory coding and billing compliance consultant in Niota, Tenn.

Do this: Divide your Medicare drug screen coding as follows:

• Use G0431 for CLIA certified high complexity lab methods using instrumented systems (durable systems capable of withstanding repeated use), such as multi-channel chemistry analyzers and chromatography/mass spectrometry systems.
• Report G0434 for CLIA waived and moderately complex tests. These include “very simple testing methods, such as dipsticks, cups, cassettes, and cards, that are interpreted visually, with the assistance of a scanner, or are read utilizing a moderately complex reader device outside the instrumented laboratory setting,” according to CMS. Note that many chemistry instruments — even many that use immunoassay methodology — are CLIA certified moderate complexity and must report to this code.

Beware of These Compliance Issues

Bundling issues, units of service, and modifiers require your attention when you’re billing Medicare for drug screening tests.

Watch units: “You should report only one unit of G0431 or G0434 per patient encounter, regardless of the number of drug classes you detect,” Zweifel says. You might have circumstances that require more than one medically necessary drug screen for the same patient on a given day, although CMS expects such instances to be rare.

Check edit pairs: The Correct Coding Initiative (CCI) bundles G0434 as a column 2 code for G0431. You cannot bill these codes together under any circumstances. That means you’ll need to select the most extensive procedure code — G0431 — if labs perform both complex and lower complexity drug screens on the same day.

Use modifier: If your lab operates with a certificate of waiver, you may perform only waived-status tests that code to G0434. When you do so, you’ll need to append modifier QW (CLIA waived test).

Laboratories with a CLIA certificate of compliance or accreditation should not append the QW modifier to claim lines, even if they perform a CLIA waived test.

Resource: To see what CMS has to say about drug screen coding, go to www.cms.gov/Outreach-and-Education/Medicare-Learning-Network-MLN/MLNMattersArticles/downloads/SE1105.pdf.