Pathology/Lab Coding Alert

CMS deletes G0430 and won't pay for 80100, 80101, 80104.

Forget everything you thought you knew about reporting drug screen tests to Medicare. With new, revised, and deleted codes for 2011, chances are you won't report your lab's drug testing the same way this year.

Questions abound: Quick on the heels of 2010 code changes and CMS's surprising 2011 reversals, many lab coders and billers are confused.

For instance: "I have been bombarded with questions regarding the terminology used with ... G0431 and 80101," says Pat Clark, BSMT(ASCP), ASCLS, healthcare consultant with Craneware, in Clarks Summit, Penn. Medicare instructed labs to use G0431 in place of 80101 (Drug screen, qualitative; single drug class method [e.g., immunoassay, enzyme assay], each drug class) in 2010 because the definitions were identical -- but they are no longer identical.

Let our experts break down the problems -- and solutions -- to make sure you get all the pay you deserve for Medicare drug screening tests.

'Complexity' Leads Your Choice

If your lab performs drug screening for single or multiple drug classes by any lab method other than chromatography, you have two codes choices to report your work for Medicare beneficiaries in 2011:

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

"It appears that you should choose between these codes 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.

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.

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.

Follow the money: The Clinical Laboratory Fee Schedule (CLFS) prices G0431 at five times G0434 (national limit amount $102.33 versus $20.47). According to CMS, "By setting the [G0431] payment at a multiple of five ..., we are recognizing that multiple drugs are often tested through one specimen and that the high complexity tests that are performed in the laboratory setting require more resources than the simple dipstick test kit tests performed outside the laboratory setting."

Confusing facts: "We've been perplexed by some details, such as the fact that we're still seeing G0431 -- the high complexity test -- listed with modifier QW (CLIA waived test)," says Bobbi Andera, BSMT, AMT, business/regulatory manager for Sanford Laboratories in Sioux Falls, S.D.

Hopefully CMS will clarify the contradictory references that occur in the following locations:

• The list of CLIA waived tests effective Jan. 1, 2011 still includes G0431 with modifier QW, despite the fact that it is no longer a waived test
• The CLFS also lists G0431 with modifier QW
• The list of CLIA waived tests effective Jan. 1, 2011 doesn't include new code G0434, but does include deleted code G0430.

Chromatography Gets Mixed Signals

Despite pricing 80100 on the CLFS, the Medicare Physician Fee Schedule (PFS) lists 80100 (Drug screen, qualitative; multiple drug classes chromatographic method, each procedure) with an "I" (invalid) code status indicator. That means the code is "not valid for Medicare Purposes. Medicare uses another code for reporting of, and payment for, these services."

In contrast, when Medicare pays for a code on the CLFS, you'll see the code listed on the PFS with status indicator "X". That means the code may be paid on a different fee schedule, such as the CLFS, because the code represents a service that "is not in the statutory definition of 'physician services'"

Best guess:"It looks like Medicare wants labs to use G0431 for chromatography instead of using 80100," says William Dettwyler, MT AMT, president of CodusMedicus, a laboratory coding consulting firm in Salem, Ore.

Problem: Although the G0431 definition could encompass chromatography -- a high complexity test -- the code requires "multiple drug classes," which the lab may not always perform. Yet you couldn't use G0434 because it states "other than chromatographic." "That leaves us with the question of how to report drug testing if the lab tests for a single drug class using chromatography," Dettwyler says.

Other Codes Won't Pay

You probably used G0430 (Drug screen, qualitative; multiple drug classes other than chromatographic method, each procedure) for some drug screen tests last year, but CMS deletes the code for 2011. CPT 2011 adds a new code with the same definition -- 80104. The intention was for Medicare to accept the new CPT code in place of G0430.

Surprise reversal: CMS deleted G0430 as expected, but declined to price 80104 for Medicare beneficiaries. In its final payment determination for the CLFS, CMS states that the 80104 code descriptor "does not accurately reflect the types of tests that need to be captured for accurate billing and payment. Instead, the descriptor for G0431 has been edited, and new test code G0434 has been created."

In other words, not only can you not use G0430 this year, you can't use 80104 either, for Medicare beneficiaries.

80101 still out: In 2010 you couldn't use 80101 because Medicare instructed you to use G0431 (with the same definition) instead. Despite changing the G0431 code definition for 2011, CMS still doesn't price 80101 on the CLFS, suggesting that you should not report that code for Medicare beneficiaries.

Bottom line: "It appears that CMS has established a two-tier drug-screen coding system -- G0431 for highly complex lab tests for multiple drug classes, and G0434 for CLIA waived or moderately complex kits or desk-top units," Dettwyler concludes. "But that may not be the final word, because CMS has promised further instruction on the matter."

Resources: Stay tuned to Pathology/Lab Coding Alert next month to learn how to report drug testing to non-Medicare payers. You can access CMS pricing information and rationale at www.cms.gov/ClinicalLabFeeSched/Downloads/CY2011-CLFS-New-Test-Codes.pdf and www.cms.gov/ClinicalLabFeeSched/02_clinlab.asp#TopOfPage.

You can learn more about CLIA test classification at www.cms.gov/CLIA/10_Categorization_of_Tests.asp#TopOfPage.