By Carol A. Filomena, MD and Amarpreet Bhalla, MD

Current Procedural Terminology (CPT) is a universal coding language first published by American Medical Association (AMA) in 1966. CPT codes are owned and maintained by the AMA. They were created to establish a uniform nomenclature for description of medical and surgical services under the Medicare Program (enacted by Congress in 1965) and for use by Blue Cross/Blue Shield and other health plans. There are several code categories.

Category I: Category I is the main and most utilized code category. Category I codes have five numeric digits and are updated January 1st of each year. Each code describes a unique procedure that must be reported with its assigned code. Food and Drug Administration (FDA) clearance must be obtained for codes or procedures that require such approval prior to Category I code assignment. Codes in Category I are for procedures or services that are performed by many physicians or other qualified health care professionals across the United States with frequencies consistent with intended clinical use, consistent with current medical practice and with established clinical efficacy as documented in the literature. Category I codes may be reported with modifier codes when applicable. When a specific Category I code is not available in the CPT code set, a code designated for an unlisted procedure is reported.

Category II: Category II codes are optional supplemental codes used to track performance measurements (PQRS codes). These codes track performance measurements developed by national organizations, evidence-based measurements and measurements that address clinical conditions of high prevalence, risk or cost. Category II tracking codes for performance measurements are released three times yearly after each AMA Editorial Panel meeting. They are updated annually in the CPT codebook.

Category III: Category III codes are temporary codes for tests and procedures that do not meet Category I criteria. They are useful for tracking number of tests performed and for research purposes. After five years the code is either deleted or an application for Category I status is requested. These codes are updated twice per year in January and July and are updated annually in the CPT codebook.

Proprietary Laboratory Analyses (PLA): PLA codes describe proprietary clinical laboratory analyses provided by a single (“sole-source”) laboratory or licensed or marketed to multiple providing laboratories. They include advanced diagnostic laboratory tests (ADLTs) and clinical diagnostic laboratory tests (CDLTs) as defined under the Protecting Access to Medicare Act (PAMA) of 2014. These analyses are of a range of tests that include multianalyte assays with algorithmic analyses (MAAA) tests and genomic sequencing procedures (GSPs). These codes are not required to fulfill Category I requirements but require commercial availability in the United States on human specimens. Each code request must come from the clinical laboratory or manufacturer that offers the test. When a PLA code is available to report a given laboratory service it must be utilized. Codes in this subsection are released on a quarterly basis to expedite dissemination for reporting and are published electronically on the AMA website. The codes in this section are also listed in Appendix O.

Appendix O – Multianalyte Assays with Algorithmic Analyses) (MAAA):  Appendix O contains MAAA codes and PLA codes. The MAAA codes are classified as either Administrative (Category I criteria not met) or as Category I. MAAAs are procedures that utilize multiple results derived from assays of various types that use algorithmic analyses. Results are typically reported as numeric scores or probabilities. An MAAA code is typically unique to a single clinical laboratory or manufacturer. MAAA codes with Category I status are also listed in the Pathology and Laboratory section in the AMA CPT codebook.

Reference: American Medical Association CPT Current Procedural Terminology 2020, professional edition, 2020 AMA