CLASSIFICATION IN ICD-10-CM

Range	Topic
A00-B99	Certain infections and parasitic diseases
C00-D49	Neoplasms
D50-D89	Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism
E00-E89	Endocrine, nutritional and metabolic diseases
F01-F99	Mental, Behavioral and Neurodevelopmental disorders
G00-G99	Diseases of the nervous system
H00-H59	Diseases of the eye and adnexa
H60-H95	Diseases of the ear and mastoid process
I00-I99	Diseases of the circulatory system
J00-J99	Diseases of the respiratory system
K00-K95	Diseases of the digestive system
L00-L99	Diseases of the skin and subcutaneous tissue
M00-M99	Diseases of the musculoskeletal system and connective tissue
N00-N99	Diseases of the genitourinary system
O00- O9A	Pregnancy, childbirth, and puerperium
P00-P96	Certain conditions originating in the perinatal period
Q00-Q99	Congenital malformations, deformations and chromosomal abnormalities
R00-R99	Symptoms, signs, and abnormal clinical laboratory findings, not elsewhere classified
S00-T88	Injury, poisoning, and certain other consequences of external causes
V00-Y99	External causes of morbidity
Z00-Z99	Factors influencing health status and contact with health services

MEDICAL CODING KEY TERMS

There are a number of important terms you’ll want to familiarize yourself with as you learn more about coding. Let’s look at some of these now.

CATEGORY (CPT)

The CPT code set is divided into three Categories. Category I, which is the largest and most commonly used, describes medical procedures, technologies and services. Category II is used for performance management and additional data. Category III houses the codes for emerging and experimental medical procedures and services.

CATEGORY (ICD)

In ICD, the category is the first three characters of the code, which describes the basic manifestation of the injury or sickness. In some cases, the category is all that is needed to accurately describe the condition of the patient, but more often than not the coder must list a more detailed description of the injury or illness (see “Subcategory,” and “Subclassification”). In ICD-10-CM, all categories are alphanumeric.

CLINICAL MODIFICATION

This designation, created by the National Centre for Health Statistics, is added to the ICD codes sets when they are implemented in the United States. Many countries expand and clarify ICD code sets for their national use; the US, for example, expanded ICD-10 from 14,000 codes to over 68,000 individual codes. This term is abbreviated “-CM” and is added to the end of the ICD code title. For instance, ICD-10-CM can be read “International Classification of Diseases, Tenth Revision, Clinical Modification.

WHO

The World Health Organization. This international body, which is an agency of the United Nations, oversees the creation of ICD codes and is one of the most important organizations in international health.

CMS

The Center for Medicare and Medicaid Services. This federal agency updates and maintains the HCPCS code set and is one of the most important organizations in healthcare today.

NCHS

The National Center for Health Statistics. The NCHS is a government agency that tracks health information, and is responsible for creating and publishing both the clinical modifications to ICD codes and their annual updates.

CPT

Current Procedural Terminology. Published, copyrighted, and maintained by the American Medical Association, CPT is a large set of codes that describe what procedure or service was performed on a patient. This code is divided into three Categories, with the first Category being the most important and widely used. CPT codes are an integral part of the reimbursement process. These codes are five characters long and may be numeric or alphanumeric.

HCPCS

Healthcare Common Procedure Coding System, pronounced Hick-Picks. This is main procedural code set for reporting procedures to Medicare, Medicaid, and a large number of other third-party payers. Maintained by CMS (See “CMS”), HCPCS is divided into two levels. Level I is identical to CPT, and is used in the same way. Level II describes the equipment, medication, and out-patient services not included in CPT.

MODIFIER

A modifier is a two-character code that is added to a procedure code to demonstrate an important variation that does not, by itself, change the definition of the procedure. CPT codes have numeric modifiers, while HCPCS codes have alphanumeric modifiers. These are added at the end of a code with a hyphen, and may provide information about the procedure itself, that’s procedure’s Medicare eligibility, and a host of other important facets. The CPT modifier -51, for example, notifies the payer that this procedure was one of multiple procedures. The HCPCS modifier –LT, on the other hand, describes a bilateral procedure that was performed only on the left side of the body.

MODIFIER EXEMPT (CPT)

Certain codes in CPT cannot have modifiers added to them. This is a fairly short list that can be found in the appendices of the CPT manual.

TECHNICAL COMPONENT

The portion of a medical procedure that concerns only the technical aspect of the procedure, but not the interpretative, or professional aspect (See “Professional component”). A technical component might include the administration of a chest X-ray, but would not include the assessment of that X-ray for disease or abnormality.

EVALUATION AND MANAGEMENT (CPT)

Evaluation and Management, or E&M, is a section of CPT codes used to describe the assessment of a patient’s health and the management of their care. The codes for visits to doctor’s office and trips to the emergency room, for instance, are included in E&M. E&M is found at the front of the CPT manual, despite being out of numerical order. The codes for E&M are 99201 – 99499.

ICD

The International Classification of Diseases is a set of medical diagnostic codes established over a hundred years ago. Maintained today by the WHO, ICD codes create a universal language for reporting diseases and injury. In the United States, we were using ICD-9-CM, while the rest of the world uses some form of ICD-10. The US too upgraded to ICD-10-CM in 2015. ICD-10-CM codes are alphanumeric. They have a three-character category, which describes the injury or disease, which is typically followed by a decimal point and three-to-four more characters, depending on the code set, which give more information about the manifestation and/or location of the disease.

SUBCATEGORY

In ICD codes, the subcategory describes the digit that comes after the decimal point. This digit further describes the nature of the illness or injury, and gives additional information as to its location or manifestation.

SUBCLASSIFICATION

The subclassification follows the subcategory in ICD codes. The subclassification further expands on the subcategory, and gives additional information about the manifestation, severity, or location of the injury or disease. In ICD-10-CM there is also a subclassification that describes which encounter this is for the doctor—whether this is a first treatment for the ailment, a follow-up, or the assessment of a condition that is the result of a previous injury or disease .

Z-CODES

Z-codes are sections of ICD-10-CM that describe patient visits related to circumstances other than disease or injury. This includes live-born infants, people with risk or disease due to family history, people encountering health services for specific or mandated evaluation or aftercare, and a host of other not easily classifiable situations.