Terminology

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Terms and Abbreviations

The following acronyms are utilized throughout Healthweb.

APC Ambulatory Patient Classification. The "Ambulatory Patient Classification" system is a set of hospital outpatient diagnoses (ICD codes) and procedures (CPT codes) grouped into broader categories that include specific Medicare prospective payment amounts for each category.

CMS The Centers for Medicare & Medicaid Services . The Center for Medicare & Medicaid Services -- formerly known as HCFA (Health Care Finance Administration) -- is the Federal agency within the U.S. Department of Health and Human Services that administers the Medicare, Medicaid and State Children's Health Insurance Programs. CMS is also responsible for Health Insurance Portability and Accountability Act of 1996 (HIPAA) and Clinical Laboratory Improvement Amendments (CLIA).

CPT Physician's Current Procedural Terminology. "Physician's Current Procedural Terminology" is a listing of descriptive terms and identifying codes for reporting medical services and procedures performed by physicians.

DRG Diagnosis Related Group. A "Diagnosis Related Group" is a payment category that is used to classify patients, especially Medicare patients, for the purpose of reimbursing hospitals for each case in a given category with a fixed fee regardless of the actual costs incurred. A DRG is based upon the principal ICD-9-CM diagnosis code, ICD-9-CM surgical procedure code, age of patient, and expected length of stay in the hospital that will be reimbursed, independently of the charges that the hospital may have incurred.

HCFA Health Care Finance Administration. Health Care Finance Administration is now known as "CMS" (see above).

HCUP Healthcare Cost and Utilization Project. A family of Health care databases and related software tools and products developed through a Federal-State-Industry partnership and sponsored by the Agency for Healthcare Research and Quality. HCUP is based on statewide data collection by individual data organizations across the United States and provided to AHRQ through the HCUP partnership.

ICD International Classification of Diseases. The "International Classification of Diseases" is a coding system developed by the World Health Organization and designed for the classification of morbidity and mortality information for statistical purposes, and for the indexing of hospital records by disease and operations, for data storage and retrieval. It is the ICD-9-CM (9th revision, Clinical Modification) diagnosis and procedure codes that are used to determine a particular DRG.

LOS Length of Stay. Length of Stay is the time spent in a hospital (measured in days) by a person who has been admitted and determined to be an inpatient. LOS is computed by totaling the number of days from the admission date through the discharge date.

MDC Major Diagnostic Category. A "Major Diagnostic Category" is one of twenty five mutually exclusive principal diagnosis categories which correspond to a single organ system or etiology and in general are associated with a particular medical specialty. MDC's are part of the larger DRG system. Each individual DRG corresponds to one distinct MDC.

APC	Ambulatory Patient Classification. The "Ambulatory Patient Classification" system is a set of hospital outpatient diagnoses (ICD codes) and procedures (CPT codes) grouped into broader categories that include specific Medicare prospective payment amounts for each category.
CMS	The Centers for Medicare & Medicaid Services . The Center for Medicare & Medicaid Services -- formerly known as HCFA (Health Care Finance Administration) -- is the Federal agency within the U.S. Department of Health and Human Services that administers the Medicare, Medicaid and State Children's Health Insurance Programs. CMS is also responsible for Health Insurance Portability and Accountability Act of 1996 (HIPAA) and Clinical Laboratory Improvement Amendments (CLIA).
CPT	Physician's Current Procedural Terminology. "Physician's Current Procedural Terminology" is a listing of descriptive terms and identifying codes for reporting medical services and procedures performed by physicians.
DRG	Diagnosis Related Group. A "Diagnosis Related Group" is a payment category that is used to classify patients, especially Medicare patients, for the purpose of reimbursing hospitals for each case in a given category with a fixed fee regardless of the actual costs incurred. A DRG is based upon the principal ICD-9-CM diagnosis code, ICD-9-CM surgical procedure code, age of patient, and expected length of stay in the hospital that will be reimbursed, independently of the charges that the hospital may have incurred.
HCFA	Health Care Finance Administration. Health Care Finance Administration is now known as "CMS" (see above).
HCUP	Healthcare Cost and Utilization Project. A family of Health care databases and related software tools and products developed through a Federal-State-Industry partnership and sponsored by the Agency for Healthcare Research and Quality. HCUP is based on statewide data collection by individual data organizations across the United States and provided to AHRQ through the HCUP partnership.
ICD	International Classification of Diseases. The "International Classification of Diseases" is a coding system developed by the World Health Organization and designed for the classification of morbidity and mortality information for statistical purposes, and for the indexing of hospital records by disease and operations, for data storage and retrieval. It is the ICD-9-CM (9th revision, Clinical Modification) diagnosis and procedure codes that are used to determine a particular DRG.
LOS	Length of Stay. Length of Stay is the time spent in a hospital (measured in days) by a person who has been admitted and determined to be an inpatient. LOS is computed by totaling the number of days from the admission date through the discharge date.
MDC	Major Diagnostic Category. A "Major Diagnostic Category" is one of twenty five mutually exclusive principal diagnosis categories which correspond to a single organ system or etiology and in general are associated with a particular medical specialty. MDC's are part of the larger DRG system. Each individual DRG corresponds to one distinct MDC.