Medical Coding Systems
Given that all healthcare system in the world ultimately need to have a billing component, the concept of data categorization is essential. To make concepts more difficult - none of these systems are static. When COVID-19 reared its face, a diagnosis code for it did not explicitly exist, and a few coding systems needed to release emergency updates so that patients could even be formally diagnosed with it from a billing perspective.
This leads us to the question well cover today - What are common coding systems in the medical domain? Given that the USA has both the largest economy in the world and simultaneously the largest healthcare system in the world as a function of GDP, it goes without saying that most of these systems are created, managed, or heavily influenced by the United States.
Diagnosis Codes
ICD-10-CM: International Classification of Diseases (10th), Clinical Modification
A U.S. adaptation of the World Health Organizations codes for diagnosing patients. There are about 70,000 of these - they can include modifiers.
W53.21XA = Bitten by squirrel
SNOMED CT: Systematized Nomenclature of Medicine - Clinical Terms
Comprehensive clinical terminology, including diagnoses, procedures, and drugs to name a few. There are hundreds of thousands of SNOMED codes and they are used internationally. It maps to several other systems.
Free to use. Managed by SNOMED International not-for profit.
44054006 – Diabetes mellitus type 2 (disorder)
Procedure Codes
ICD-10-PCS: International Classification of Diseases (10th) , Procedure Coding System
Codes for inpatient procedures.
4A133B1 = Monitoring of Arterial Pressure, Peripheral, Percutaneous Approach
CPT (HCPCS Level 1): Current Procedural Terminology
Codes for outpatient procedures.
The full list requires a license to access, and are managed by the AMA.
99397 = preventive exam for patient over age 65
HCPCS (AKA HCPCS Level 2): Healthcare Common Procedure Coding System
Describes non-physician services, supplies, and durable medical equipment (DME), as well as drugs.
A4670 = Automatic blood pressure monitor
SNOMED CT: Previously Mentioned.
Lab Codes
LOINC: Logical Observation Identifiers Names and Codes
Codes for lab tests and clinical observations.
Free to use, managed by the Regenstrief Institute.
85354-9 – Blood pressure panel with all results
SNOMED CT: Previously Mentioned.
Drug Codes
Created by CDC to categorize vaccinations and immunizations
20 = diphtheria, tetanus toxoids and acellular pertussis vaccine (DTaP)
Nomenclature for clinical drugs, maintained by the U.S. National Library of Medicine.
RX10359383 = ciprofloxacin 500 mg 24-hour extended-release
NDC: National Drug Code
Identifies medications and packaging in the U.S. maintained by FDA.
Includes drug, label, product, and package code - May be 9 to 12 digits long.
55111-422-78 = ciprofloxacin hydrochloride tablet, film coated, extended release
GPI: Generic Product Identifier
2 to 14 digit identifier created by Wolters Kluwer's Medi-Span for drugs
58-20-00-60-10-01-05 = Antidepressants, Tricyclic agents, Nortriptyline, Hydrochloride, Capsule, 10mg
SNOMED CT: Previously Mentioned.
Medical Device Codes
UDI: Unique Device Identifier
For identifying and tracking medical devices mandated by the USE government in 2007.
Each code describes all information about a medical device.
(01) 101123456789 (17) 210415 (10) LOT12345 - Medtronic HeartValve for a specific person.
Human Codes
SSN: Social Security Number
Unique identifier for U.S. residents, often used in administrative contexts.
Decreasingly used due to risk of breach and the impacts it can have on a patient.
10 digits (XXX-XX-XXXX)
Member ID / MRN:
Identifier assigned by health insurance companies (Member ID) or provider (MRN).
Increasingly used over SSN due to lower risk should a data breach occur.
Undefined Structure
NPI: National Provider Identifier
Identifier for healthcare providers in the U.S.
Offered in a national registry, though information is often not up-to-date
10 digits (XXXXXXXXXX)
Used for classifying race and ethnicity.
2058-6 = African American.
Genetic Codes
OMIM: Online Mendelian Inheritance in Man
tens of thousands of indexed phenotypes and genes
03933 = MICROVASCULAR COMPLICATIONS OF DIABETES, SUSCEPTIBILITY TO, 1; MVCD1
Government / Insurance Codes
HCC: Hierarchical Condition Category
Risk adjustment coding system for chronic conditions used by payers to incrementally describe a population.
HCC19 = Diabetes without complications
CDPS: Chronic Illness and Disability Payment System
One of the three Medicaid programs used by US states low-income individuals.
PSYML = Psychiatric, medium low
HEDIS: Healthcare Effectiveness Data and Information Set
Performance measurement tool for preventative care performed by health plans.
COL = Colorectal Cancer Screening
DRG: Diagnosis-Related Group
Coding system used for hospital billing and reimbursement.
689 - KIDNEY & URINARY TRACT INFECTIONS W MCC
UB-04: Revenue Codes
billing format used by healthcare providers to submit claims to Medicare, Medicaid, and private insurers for services rendered in institutional settings, created by National Uniform Billing Committee.
013X = Hospital Outpatient
Conclusion
Coding systems in the medical domain are essential for accurate billing, diagnosis, and treatment tracking. They provide a standardized language for healthcare providers, insurers, and government entities, ensuring clarity in communication and proper reimbursement. These systems, such as ICD-10-CM, SNOMED CT, CPT, LOINC, RxNorm, and others, enable the efficient exchange of health data, allowing for more consistent patient care. With the healthcare landscape constantly evolving, these systems are regularly updated to address emerging challenges, such as new diseases or treatments, ensuring that healthcare systems worldwide can adapt to changing needs while maintaining accuracy and compliance.
If you are interested in abstracting or using any of these systems for predictive modeling reach out to us and we will by happy to share our solutions around these systems and more!