Before Medicare pays for any test or diagnostic service, two basic criteria must be met:

(1) the service must be covered by Medicare (e.g., certain procedures such as routine screening tests are not covered) and

(2) the service must be medically necessary or indicated.

Once these two criteria are met, Medicare pays for most clinical laboratory tests based on the Laboratory Fee Schedule. Each carrier publishes a unique laboratory fee schedule and adjusts payment levels annually on January 1st based on Congressional budget recommendation.

Medicare payment for clinical laboratory tests is always the lesser of the fee schedule amount or the actual amount billed. The provider must accept the Medicare reimbursement as payment in full for a laboratory test. Medicare patients may NOT be billed for any additional amounts. Tests must be billed directly to Medicare by the laboratory or physician performing the test. If an outside laboratory performs a test on a referral from a physician, only the reference laboratory may legally bill Medicare for the procedure.

Procedure (CPT) Codes and Modifiers

The CPT codes for Glycated Hemogobin (A1c) determinations are:

83036 Hemoglobin; glycated (A1c)
83036QW Hemoglobin; glycated (A1c) using CLIA waived method

Medicare reimbursement for CPT codes 83036 and 83036QW is $13.42 in all states except:

Idaho: $9.66 Maryland: $12.66 Oklahoma: $11.95
Rhode Island: $12.09 South Dakota: $12.86 Wyoming: $10.49

Correct DOS FOR Clinical lab services

The DOS is the date the specimen was collected. If the specimen is collected over a period that spans two calendar dates, the DOS is the date the collection ended. This would include the collection fee, services provided in a physician laboratory, in a clinical laboratory, and/or a reference laboratory.