Biomedical Engineering and Design
Codes and Classifications
Health care reimbursement is complex.
1. Overview of some codes and how they're used for payments (as of September 2020)
- ICD-10-CM (Clinical Modification) = diagnoses
- ICD-10-PCS (Procedure Coding System) = procedures
- CPT (Current Procedural Terminology) = part of HCPCS
- HCPCS (Healthcare Common Procedural Coding System) : Level I is the CPT, and Level II is mainly for identifying products, supplies, and services that are NOT included in the CPT, such as ambulance services; drugs; devices; and "durable medical equipment, prosthetics, orthotics, and supplies" (DMEPOS), used in outpatient settings such as hospital outpatient departments, physicians' offices, and patients' homes
ICD (International Classification of Diseases) is maintained by the CDC with the authorization of World Health Organization, and is international.
CPT (Current Procedural Terminology) is maintained by the American Medical Association, and is United States only.
CPT -- Current Procedural Terminology
- The American Medical Association produces this annual list to classify and report medical services and procedures.
--- Overview of what CPT codes are, and descriptions of CPT categories I, II, and III
--- Look up CPT codes for free on the AMA website (create a free account, and click "agree" for the terms)
--- You can also look around the web for CPT codes, but please add site:.gov to your search (so that you get U.S. government results), and/or get *several* results from the web, so that you can verify that the code you found is correct
- Public and private health insurance programs depend on CPT codes to describe medical, surgical, and diagnostic services, to manage reimbursements, and to facilitate reliable nationwide communication among physicians, other healthcare providers, patients, and third parties.
HCPCS -- Healthcare Common Procedure Coding System
The HCPCS has two levels:
- CPT (whose information is on the previous tab)
- DMEPOS -- For "products, supplies, and services NOT included in the CPT codes, such as ambulance services and durable medical equipment, prosthetics, orthotics, and supplies (DMEPOS) when used outside a physician's office."
--- This system was created to identify services, supplies, and equipment that are not included in the CPT but which *are* covered by Medicare and other insurers.
- Unlike the CPT and ICD, you *cannot* search this with keywords, but only with the DMEPOS code itself
- The easiest way to find those is by searching the open web, but look at more than one source to make sure you've found the correct code
HCUP (Healthcare Costs and Utilization Project) and HCUPnet
Background (the link to the HCUPnet database is below, clearly labeled)
- The Healthcare Cost and Utilization Project (HCUP) collects the data from "State data organizations, hospital associations, private data organizations, and the Federal government," and "includes the largest collection of longitudinal hospital care data in the United States," beginning in 1988. HCUP is run by the Agency for Healthcare Research and Quality (AHRQ).
- HCUPnet has databases of inpatient, ER, and ambulatory surgery statistics. These are estimates based on a sampling of data provided by each state. All 50 states participate in the inpatient sample, but the outpatient statistics are only provided by states representing about 2/3 of the U.S. population.
- HCUP data come in two types: The underlying datasets, which require some red tape and the use of statistical software such as SPSS; and HCUPnet, which is an online search tool providing immediate results. So always start with HCUPnet.
National statistics -- updated annually
State statistics -- updated as new state data are processed
Note: There is at least an 18-month lag between the end of the calendar year and the availability of the Nationwide Inpatient Sample (NIS)
NOTE: As of 2021, ICD-10 codes are no longer available *within* HCUPnet.
-- (Find ICD-10 codes from the WHO or the CDC)
"We apologize for the inconvenience, but the option to query individual ICD-10-CM/PCS codes for utilization and outcome statistics has been disabled, because the results may not be indicative of the intended clinical/surgical concept.
"Individual ICD-10-CM diagnoses or ICD-10-PCS procedures often need to be reported in combination to define a clinical/surgical concept, because of the specificity of the individual codes. The ICD-10-CM Coding Guidelines provide a number of examples.
----Table of Contents of the Guidelines: pp.2-6; very helpful
----Section I: structure and conventions of the classification and general guidelines that apply to the entire classification, and chapter-specific guidelines that correspond to the chapters as they are arranged in the classification
----Section II: guidelines for selection of principal diagnosis for non-outpatient settings
----Section III: guidelines for reporting additional diagnoses in non-outpatient settings
----Section IV: for outpatient coding and reporting
"HCUPnet does provide the ability to query clinical conditions and surgeries by the Clinical Classification Software Refined (CCSR), which aggregates ICD-10-CM/PCS into clinically meaningful categories, for the HCUP National Inpatient Sample (NIS) data and Nationwide Emergency Department Sample (NEDS) data.
"As an alternative, frequencies of ICD-10-CM/PCS codes (individually and by the CCSR categories) will be available in the Documentation section of each nationwide database on the HCUP User Support website. Currently, the frequencies of ICD-10-CM/PCS codes reported in the HCUP NIS are available at https://hcup-us.ahrq.gov/db/nation/nis/nisdbdocumentation.jsp.
- "For any HCUP database, tool, or product-related questions, please visit the HCUP FAQ page at www.hcup-us.ahrq.gov/tech_assist/faq.jsp or contact User Support at email@example.com."
HCUPnet (the database itself)
--- (Free, short, interactive tutorial; recommended)
- On the HCUPnet page, choose "Create a new analysis"
- "Inpatient" will get you the most information
- NOTE: The numbers in "Emergency Department" and in "Ambulatory Surgery" only represent patients from about 2/3 of U.S. hospitals. Therefore, multiply the numbers you get by 3/2.
- Note: "Trends" has data only through 2014 (and uses ICD-9).
- When you're done, create analysis. Understanding the results can be difficult sometimes -- this methodology page is long, but gives more detail, definitions, and other info.
Refining Your Results
The blue navigation bar on the left includes several ways to focus your results, including:
- results by patient or hospital characteristics
- settings of care, geography, and year of analysis
- all-listed vs. principal diagnosis or procedure (remember that principle will not include patients who had the diagnosis as a secondary or tertiary problem, so think about whether you want ONLY that main diagnosis, or ALL patients who had it, no matter what else they had).
Your results can also be graphed and exported (click SUBMIT at the bottom to make your changes).
Note: Some selections on the blue navigation bar might be greyed out; this could be because of the database type, data year (after 2015, when ICD-10-CM/PCS codes were introduced); principal versus all-listed diagnosis (procedure); or other reason.
To clear your selections, either go back to the home page (this will clear everything), or change your selections on the blue navigation bar, and click SUBMIT again.
ICD - International Classification of Disease
ICD-10 became the official version on October 1, 2015.
- The ICD is used to code signs, symptoms, injuries, diseases, and conditions
- It standardizes reporting of illness, death, and medical procedures; and the classification of diseases and other health problems recorded on many types of health and vital records, such as death certificates
- This allows the compilation of national mortality and morbidity statistics by WHO Member States, which is also essential for compiling of statistical info about diseases in a format that allows international comparison of those data.
- "World Health Organization (WHO) authorized the publication of the International Classification of Diseases10th Revision (ICD-10), which was implemented for mortality coding and classification from death certificates in the U.S. in 1999. The U.S. developed a Clinical Modification (ICD-10-CM) for medical diagnoses based on WHO’s ICD-10, and CMS developed a new Procedure Coding System (ICD-10-PCS) for inpatient procedures." (From CDC)
- Dynamed and Micromedex also gives ICD-10 codes; search the medical condition and you'll see "ICD Codes" on the left
- Ignore "GEMS" (General Equivalence Mappings) if you see it mentioned; that's the translation to and from ICD-9 and ICD-10 codes, and 2018 was the last one
ICF -- International Classification of Functioning, Disability, and Health
This classification was created by the World Health Organization (WHO) and approved in 2001.
Its purpose is to provide a "framework for measuring health and disability at both individual and population levels."
The WHO page about the ICF includes:
(Remember that this framework is only one piece of a complicated landscape!)