What’s the Difference Between CPT and ICD Codes?

If you’re considering a career in medical billing and coding you may be confused by the acronyms in the curriculum. If you’re wondering what’s the difference between CPT and ICD codes, here’s a concise description of the two coding systems you’ll need to learn in order to enter the field.

What are CPT and ICD?

ICD is the acronym for International Statistical Classification of Diseases and Related Health Problems.
ICD is published and maintained by the World Health Organization (WHO) in order to be used universally as a standard for diseases as well as social, traumatic and environmental aspects of bodily injury.
CPT is the acronym for Current Procedural Terminology.
This is the code used to describe the procedures, diagnoses, and services a patient has received during their medical appointment. A CPT is usually five digits long and is the language used between the physician’s office or hospital and the insurance company that pays the medical bill. Because there is a specific CPT code for each notation on a chart the CPT code is more expansive than the ICD code.

How are They Used?

Once a patient has been examined by a physician, the coder reads the patient record and assigns an ICD for each diagnosis, disease or injury the doctor has notated on the chart. Often the coder will speak directly to the doctor or nurse in order to clarify a specific injury or other health problem so accuracy of their ICD notation is ensured. The patient chart will then go to the biller for the next stage in the process. Every issue and symptom a patient has will be assigned a corresponding ICD code. The biller reads the ICD notations and transfers the information into CPT codes for the purpose of submitting the patient bill to the insurance carrier. For example, if the ICD code is for a fractured femur the biller will match the ICD for that injury to the corresponding CPT code that indicates payment for that treatment. The biller is responsible for properly filling out the insurance form with the accurate billing information, submitting the form to the insurance company and tracking any co-payments or deductibles not covered by insurance. The patient can then be billed for the balance not covered. CPT and ICD codes are vital to the medical profession because they insure a smooth payment system between physicians and insurance companies. Without the coding system in place a patient would need to pay up front for treatment and wait for their insurance carrier to examine their patient record and then reimburse them for monies spent.

Is One Used More than the Other?

While both codes are used evenly within the hospital or office system, the ICD coding system is used more often than CPT codes. This is because the ICD is an international system, meaning it is a standard used throughout the world. By having a uniform code such as the ICD, medical professionals can communicate information about treatments and illnesses in every country, regardless of any language barriers that may exist.

Are the Codes Used for More than Billing?

If a patient visits another doctor or hospital, anywhere in the world, the examining physician can immediately know what previous problems they’ve had as soon as they examine the patient chart and read the ICD codes. ICD codes cover every imaginable disease and problem, including x-rays, surgery and lab tests. Because the ICD codes are alpha-numeric, they can be assigned to every diagnosis and symptom as well as cause of death.
A good way to remember the difference is the ICD code is a precise system of communication to create accuracy within the medical profession, and the CPT code promotes accurate communication between the patient, physician and insurance company. They are also used for statistical purposes as they are perfect for compiling and analyzing data in regard to diseases and all other medical problems, as well as the types and frequency of treatments and diagnoses.
For example, by compiling the statistical data of ICD codes throughout the world, WHO is able to track the presence of communicable diseases such as measles or influenza. They can then use the data to pinpoint current outbreaks as well as predict whether the outbreak is waning or getting bigger. This is how organizations such as the CDC predict how bad an influenza outbreak will be, as well as the specific strains that are being reported by every country of the world.


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