Modifier Coding Alert

Medicare will deny test claims that don’t include the CLIA waived test modifier.

If your practice performs in-office lab services, you need to know what clinical laboratory improvement amendments (CLIA) certification you have, so you know whether you’ll need to add a modifier to your claim.

Read the conditions for using modifier QW to identify whether your practice is qualified to report in-office lab services and what you need to do to get paid.

Wave Goodbye to QW Denials

You’ll use informational modifier QW (CLIA waived test) on lab service codes that are on the CLIA list of tests waived from regulatory oversight.

“The modifier QW indicates that the procedure is one that personnel with minimal skills in laboratory testing may be able to perform with a low risk that they will perform the test incorrectly,” says William K. Dettwyler, M.T., president of Codus Medicus, Inc. in Salem, Ore. “It is usually a test that is known as a single step process that requires minimal handling, such as dipping the coated stick in the urine and then reading the result compared to a color chart or graph.”

Example: Your physician orders a non-instrumented drug screening (G0434, Drug screen, other than chromatographic; any number of drug classes, by CLIA waived test or moderate complexity test, per patient encounter) using a kit that will test for 12 drugs (THC, COC, OPI, mAMP, AMP, PCP, BZO, BAR, MTD, OXY, MDMA, and BUP). If your practice is CLIA-waived certified, you will report G0434-QW. If your practice is only qualified to perform waived testing and neglects to add modifier QW, the payer will deny payment as lab not certified, Dettwyler says.

Caution: Labs with a CLIA certificate of compliance or accreditation can perform non-waived tests and should not append modifier QW with those tests.

Be Aware of These Important Points

There are conditions to be aware of before you start appending QW to your codes. When your practice holds a certificate of waiver, it limits the lab to perform only tests that CMS considers as waived tests under CLIA and the tests change quarterly. Your practice can also only use kits that are FDA classified as CLIA waived.

You can’t bill with modifier QW if the test or test kit are not waived. If the test and kit are waived, Medicare can still deny the lab test claims if you do not attach QW to the test code. Using modifier QW doesn’t change the actual amount you get reimbursed, but if you forget the modifier, you may not get paid at all.

Reminder: Other payers may have different rules than Medicare for QW. You need to contact your non-Medicare payers to see what they require.