Medical CPT Codes: What is CPT?

Medical bills are claims for payment for the services provided the healthcare providers. Billings are usually submitted to insurance companies or to government agencies responsible for Medicare and Medicaid. The bills follow formats that insurers and agencies require to understand the services that were provided and the fees that should be paid to the providers.

When a doctor provides a service, a medical coder translates that service into a specific code that describes the service provided. Those codes appear on medical bills.

Medical coders generally assign two kinds of codes. When a physician diagnoses a health condition, the coder assigns a diagnostic code that describes the condition. When a physician provides a service or procedure to a patient, the coder assigns a CPT code that describes the service or procedure.

Doctors perform a large variety of services for patients. While many other professionals bill by the hour, insurance companies typically pay by the procedure. To standardize payments, insurers and government benefit providers need billings to reflect the precise procedure or service being billed. While that could be accomplished using words, medical billings reduce those words to numerical codes called Current Procedural Terminology (CPT) codes.

The American Medical Association (AMA) developed CPT codes to facilitate billing, but the codes serve other purposes, as well. For example, CPT codes make it possible to gather statistical information about the frequency with which the same procedures are performed in different areas of the country.

The AMA first developed CPT codes in 1966. The AMA has revised and expanded the coding system on several occasions. The Centers for Medicare & Medicaid Services, which oversees the Medicare and Medicaid programs, incorporated the AMA’s CPT codes into its own system, the Healthcare Common Procedure Coding System (HCPCS).

The AMA has established a CPT Editorial Panel to update the CPT coding system based on changes in medical practices, treatment methods, and technologies. The CPT Editorial Panel consists of independent expert volunteers from different sectors of the health care industry. They receive input from physician advisors who are nominated by medical specialty societies.

The AMA’s CPT codes have become the default coding system for medical bills, in part because the government requires CPT codes to be used as part of the HCPCS system for Medicare and Medicaid billing. Most private insurers regard the CPT codes as their preferred coding system for medical billings.

The bulk of CPT codes are known as Category I codes. These are 5-digit codes that describe most medical procedures and services.

Category I codes are divided into six sections. The most frequently used CPT codes are found in the Evaluation and Management Services section. These codes describe office visits, examinations, inpatient hospital visits, consultations, emergency department visits, counseling, newborn care, and other patient care services.

Category I codes range from 99091 to 99499. For example, CPT code 99212 refers to an office or outpatient visit with an established patient that takes less than 20 minutes. Different codes for outpatient visits apply to new patients or to patient visits that take a longer time.

The remaining five sections of Category I codes are:

1. Anesthesia Services (01000 – 01999)
2. Surgery (10021 – 69990)
3. Radiology Services (70010 – 79999)
4. Pathology and Laboratory Services (80047 – 89398)
5. Medical Services and Procedures (90281 – 99607)

The Medical Services and Procedures section overlaps numerically with Evaluation and Management Services, but refers to specific services such as vaccinations, dialysis, and ophthalmology services.

Category II codes are supplemental tracking codes (also known as performance measurement codes). Category II codes are not linked to fees or billing. Physicians use Category II codes to track information about patients. The codes consist of four digits and the letter F. They cover topics that include patient history, physical examination results, test results, and patient outcomes.

Category III codes are temporary tracking codes that apply to new and emerging technologies. The FDA uses Category III codes to collect data that might help it assess new technologies. Category III codes also describe new procedures that may justify a new Category I code if use of the procedure becomes widespread. Category III codes consist of four digits and the letter T. They do not affect patient billings.

Modifiers are two-digit codes (two numbers, two letters, or one of each) that are added to other CPT codes to provide additional information. Modifiers provide additional information about the service or procedure described in a CPT code. For example, a modifier might describe the location on the body where a procedure was performed. Other modifiers (sometimes known as pricing modifiers) affect the accuracy of billings.

The failure to use modifiers can result in excessive billings. For example, in some cases a physician will perform more than one surgical procedure at the same time. The billing coder should select a CPT code that describes the performance of those procedures together.

In some cases, a physician might think that the procedures took an unusually long time and will instruct the coder to bill each procedure as if they were performed at different times. The coder should instead add an appropriate modifier that indicates the procedure took more time than the CPT code anticipates. The process of billing separate procedures (known as “ unbundling ”) rather than using the correct CPT code plus a modifier will generally result in excessive billing.

Decoding CPT codes does not require a medical degree, but it does require an understanding of medical terminology and familiarity with the intricacies of the CPT coding system. Medical billing experts help lawyers and patients understand whether medical billings are accurate or inflated by comparing CPT codes to medical records.

Medical records often fail to support the CPT codes that coder selected. When the coder uses a code for a more expensive procedure than the patient received or unbundles procedures that were performed at the same time, medical bills are inflated. While medical billing experts use various techniques to help lawyers and patients understand whether medical bills are reasonable, that process usually begins by determining whether the CPT codes on the billing match the services and procedures that were actually provided.