Question

Define and explain classification and vocabulary systems and to compare and contrast the impact of each system on both inpatient and outpatient medical coding. Explain the SNOMED CT vocabulary system and the different types of health care classification systems (ICD-10-CM, ICD-10-PCS, and CPT) and provide a brief history of each classification. Write a minimum of 750 words.

Answer 1

Clinical coding constitutes one of the fundamental functions in the field of health information management (HIM).It can be defined as “designating descriptions of diseases, injuries, and procedures into numeric or alphanumeric designations. It involves the use of a health record as the source for determining code assignment..”Clinical classification systems and clinical terminologies represent two distinct sets of coding schemes that are used in healthcare. In reality, these concepts—clinical terminology and classification-—are often used incorrectly and interchangeably.

A reference terminology can be defined as “a set of concepts and relationships that provide a common reference point for comparisons and aggregation of data about the entire health care process, recorded by multiple different individuals, systems, or institutions.”⁴ Systematized Nomenclature of Medicine–Clinical Terms (SNOMED CT) represents an example of clinical terminologies used in healthcare. SNOMED CT is a standardized healthcare terminology that was originally developed from a pathology-specific nomenclature called Systematized Nomenclature of Pathology. SNOMED CT is a controlled medical terminology that encompasses diseases, clinical findings, etiologies, procedures, and health outcomes.^{5, 6} It can be used by physicians, nurses, allied health professionals, veterinarians, and researchers.

SNOMED CT is defined by the International Health Terminology Standards Development Organisation (IHTSDO) as “SNOMED CT is a comprehensive clinical terminology that provides clinical content and expressivity for clinical documentation and reporting. SNOMED CT contains concepts for both human and non-human medicine.”SNOMED CT is basically comprised of concepts, descriptions, and relationships in order to accurately represent clinical information in healthcare.

The ownership, maintenance, and distribution of SNOMED CT was originally the responsibility of the College of American Pathologists, but this responsibility was transferred to the IHTSDO in 2007.The current version of SNOMED CT is available at no charge through the National Library of Medicine (NLM). The US license for SNOMED CT was obtained by the NLM through the Unified Medical Language System project.SNOMED CT can be used to support direct patient care, clinical audit, research, epidemiology, and service planning. Furthermore, “the global scope of SNOMED CT reduces geographical boundary effects arising from the use of different terminologies or coding systems in different organizations and countries.”

A classification is “a system that arranges or organizes like or related entities.”Classification systems are intended for classification of clinical conditions and procedures to support statistical data analysis across the healthcare system. Classification systems can provide standards for comparisons of health statistics at national and international levels. Also, classification systems can be used to support other applications in healthcare, including reimbursement, public health reporting, quality of care assessment, education, research, and performance monitoring.The International Classification of Diseases, Tenth Revision, Clinical Modification and International Classification of Diseases, Tenth Revision, Procedure Coding System (ICD-10-CM/PCS) represents an example of the clinical classification systems. It is the US clinical modification of the World Health Organization (WHO) International Classification of Diseases, Tenth Revision (ICD-10). ICD-10-CM/PCS replaced ICD-9-CM on October 1, 2015, in the United States.

The National Center for Health Statistics and the Centers for Medicare and Medicaid Services (CMS) are the US governmental agencies responsible for overseeing all changes and modifications to the ICD-10-CM/PCS.

Coding Clinical Expressions

The two sets of systems were designed to serve different purposes and therefore are intended to satisfy different user requirements. SNOMED CT is designed for input into electronic health record (EHR) systems and other clinical applications, while ICD-10-CM/PCS is basically designed for providing outputs in terms of reports and statistics. Therefore, each system has a unique hierarchical structure to serve the purposes for which it was originally intended. It provides a brief description of how to code the clinical expression “pain in right leg” using a clinical terminology (SNOMED CT) and a classification system (ICD-10-CM).

However, coding in SNOMED CT is different from conventional coding using ICD-10-CM/PCS. Coding using SNOMED CT is always automated: end users cannot view the codes assigned by the system. For this reason, SNOMED CT is being used by software developers and EHR vendors in order to facilitate communication between different applications through creating a standard language. In fact, we can think of SNOMED CT as a programing language; users utilize applications that apply SNOMED CT without knowing what is at work in the background. For example, SNOMED CT has been combined with natural language processing (NLP) to improve EHR capabilities. In this case, SNOMED CT could identify where a condition exist or not or when it should be ruled out because of the set of concepts and attributes that could further clarify a certain case. If such capabilities are enabled, SNOMED CT could be used for generating alerts and reminders or as part of the decision-support system to identify contradictory notes and improve the quality of patient care.

In contrast, ICD-10-CM/PCS coding is performed by professional coders, who used to manually assign codes to patients’ diagnoses and procedures. With the advancement of technology, coders have been using special encoders or computer-assisted coding (CAC) applications. CAC applications can facilitate accurate and efficient coding by automatically suggesting codes based on the clinical documentation in the EHR system. Thus, ICD-10-CM/PCS coding is semi-automated at best and requires human intervention to either assign or validate selected codes.

However, essential elements distinguish a clinical terminology from a classification system. Before concluding which system is “best” to accommodate healthcare needs and data structure, a critique of both systems will be presented in the following section using the American Health Information Management Association (AHIMA) Data Quality Management (DQM) model. The AHIMA DQM model was chosen as a framework for assessment for the following reasons:

1. AHIMA’s DQM model can provide a standard for comparison as well as an objective assessment of totally different systems with varying scopes and applications.
2. AHIMA’s DQM model was developed to accommodate complexity of healthcare data by providing a way to quantify the quality of healthcare data and the attributes of the data.
3. No other relevant models can replace the AHIMA’s DQM model in this capacity, making it a long-established health information standard.

SNOMED CT and ICD-10-CM/PCS will be utilized as examples of clinical terminologies and clinical classification systems, respectively.