Clinical documentation is the backbone of accurate, efficient care. To ensure the necessary detail is captured, most organizations rely on foundational code systems like ICD-10-CM and SNOMED CT®, but specialized terminologies that exist alongside these standards are equally essential – particularly in fields like oncology, rare disease research, and behavioral health. Yet, these specialty vocabularies often receive far less attention than they deserve.
That’s unfortunate, because they ensure clinicians can document with the precision their specialties require, supporting billing and regulatory needs and generating high-quality data for downstream uses such as population health, payer analytics, and life sciences research. When clinicians have more comprehensive terminologies and codes at their fingertips, they spend less time searching for approximations and more time focused on patient care. That same clinical specificity enables precision medicine initiatives, the generation of real-world evidence, and life sciences research that rely on consistent, high-fidelity clinical data.
For example, oncology teams require detailed morphology and topography that general code sets simply don’t provide. Behavioral health clinicians need terminology that accurately captures complex symptoms and developmental considerations. And life sciences organizations rely on consistent, structured data to identify cohorts and evaluate outcomes across research sites.
Across revenue cycle management, payer operations, and clinical research, the ripple effect is the same: stronger documentation reduces administrative burden and improves the reliability of the data used for critical decision-making.
To understand how this added specificity shows up in practice, it’s helpful to examine the specialized terminologies that support documentation and data quality across different clinical and research domains.
Mondo/OMIM
What is it?
Monarch Disease Ontology (Mondo) is a logic-based structure that relates many disease ontologies and terminologies to each other from multiple industry-leading vocabularies like OMIM, Orphanet, and ICD-10-CM. OMIM (Online Mendelian Inheritance in Man) is an authoritative catalog of human genes, genetic disorders, and traits that serves as a key reference within the Mondo framework.
How or why is it used?
Mondo and OMIM are used by researchers, clinicians, and others in the biomedical community for rare disease research. Mondo standardizes genotype, phenotype, and other disease-related concepts, creating a unified foundation for discovery. OMIM, as a core reference within Mondo, supports genetics research, clinical education, and clinical genetics practice. It also aids in understanding relationships between diseases and genes.
Why it matters
Mondo bridges gaps between disparate disease information by cross-referencing source terminologies with precise semantics. OMIM enriches this structure by describing how genetic and environmental factors influence disease manifestations. Together, they support earlier diagnosis, more accurate classification, and better-informed research for rare disease populations, which in turn enables more precise cohort identification and helps connect eligible patients to specialized treatments and clinical trial opportunities.
Example
Diagnosis: Primary ciliary dyskinesia
ICD-10-CM: Single, broad respiratory malformation category
MONDO/OMIM: Structured disease family with dozens of genetically distinct subtypes
DSM-5-TR and DC:0-5
What is it?
The Diagnostic and Statistical Manual of Mental Disorders (DSM®) is a clinical reference manual created by the American Psychological Association (APA) for referencing and documenting behavioral health diagnoses. The DC:0-5, or Diagnostic Classification of Mental Health and Developmental Disorders of Infancy and Early Childhood supports behavioral health assessments in infants and toddlers.2
How or why is it used?
Both manuals are used to aid mental health professionals in assessing and appropriately diagnosing individuals with behavioral health concerns. They work alongside ICD-10-CM to create a shared diagnostic language for documentation, care coordination, and billing.3
Why it matters
Without the detailed terminology included in these manuals, it would be far more difficult for providers to properly assess and document behavioral health diagnoses in the EHR including variations in presentation, duration, and developmental context. The needs of children introduce additional complexity, which is why DC:0-5 is so critical for early childhood care. A fully specified, APA-compliant DSM-5 diagnosis captures a level of clinical detail that ICD-10-CM simply cannot, making DSM-based terminology essential for accurate, high-fidelity behavioral health documentation.
Together, these specialized terminologies help clinicians document what they observe with clarity and consistency. This leads to more appropriate interventions, quicker reimbursement, and more reliable data for population-level insights. Without this level of detail, patients with specific behavioral health subtypes or severity levels may become effectively invisible in structured data – preventing them from being identified for the most appropriate treatments or clinical trial opportunities.
Example
Diagnosis: Anxiety-related disorders
ICD-10-CM: Generalized diagnosis with limited clinical context
DSM-5-TR and DC:0-5: Diagnosis includes symptom patterns, severity, duration, and developmental context
ICD-O-3.2
What is it?
ICD-O-3.2 is a classification system associated with the World Health Organization’s (WHO’s) International Classification of Diseases system that is specifically designed for use in oncology care.
How or why is it used?
ICD-O-3.2 is primarily used to communicate information about the pathology of cancerous tumors. Specifically, it categorizes cancerous tumors based on morphology, including cell type, behavior, and site (topography).
Why it matters
ICD-O-3.2 is essential for oncologists who need detailed information about a tumor’s histology and site. This level of specificity is not available in broader classifications like ICD-10-CM. For instance, a researcher looking for inflammatory carcinomas of the breast would locate that information using ICD-O codes.
This granularity enables consistent tumor classification, clarifies disease staging, and distinguishes primary from metastatic lesions. It also supports organizations like the National Cancer Institute (NCI), the National Program of Cancer Registries (NPCR), and the Centers for Disease Control and Prevention (CDC) as they track cancer prevalence and survival rates across the U.S.
Example
Diagnosis: Primary infiltrating ductal carcinoma of lower inner quadrant of left breast
ICD-10-CM: Malignant neoplasm of lower-inner quadrant of left female breast
ICD-O-3.2:
Morphology: Infiltrating duct carcinoma, NOS
Topography: Lower inner quadrant of breast
Histological grade: Grade or differentiation not determined, not stated or not applicable
The limits of ICD-10-CM: Why precision requires specialty vocabularies
While ICD-10-CM remains foundational for clinical documentation and billing, it was never designed to capture the depth of information required in many specialty domains. In fact, the ICD system was originally developed to classify causes of death, not to support nuanced clinical documentation across complex conditions.
Oncology, genetics, behavioral health, and other specialized areas require levels of detail that ICD-10-CM cannot express on its own. Specialty terminologies fill these gaps by enabling more structured, specific documentation – reducing ambiguity and ensuring that critical clinical distinctions are captured accurately.
Precision terminology that serves the entire healthcare ecosystem
Specialty terminologies play a foundational role in modern healthcare by ensuring that clinical data reflects the true complexity of care being delivered. When documentation is supported by the right vocabularies, clinical information becomes more precise, more reliable, and more useful beyond the point of care.
High-quality data begins with high-quality terminology. And when specialty vocabularies are available within the EHR, organizations are better equipped to support research, analytics, and patient access to emerging therapies.
IMO Core supports ICD-O-3.2, DSM-5-TR, Mondo/OMIM, and more – embedded directly in EHR workflows. Schedule a demo to see how this could help your organization at imohealth.com/schedule-a-demo.
1Vasilevsky N, Matentzoglu N, Toro S, et al. Mondo: Unifying diseases for the world, by the world. medRxiv. Accessed via: https://www.medrxiv.org/content/10.1101/2022.04.13.22273750v3.article-info
2DC:0-5 Manual and Training. ZERO to THREE. Accessed via: https://www.zerotothree.org/our-work/learn-professional-development/dc0-5-manual-and-training/
3Frequently asked questions. American Psychological Association. Accessed via: https://www.psychiatry.org/psychiatrists/practice/dsm/frequently-asked-questions#:~:text=DSM%20contains%20 descriptions%2C%20symptoms%20and
SNOMED and SNOMED CT® are registered trademarks of SNOMED International
DSM®, DSM-IV®, DSM-5® are registered trademarks of the American Psychiatric Association, and are used with permission herein. Use of these terms is prohibited without permission of the American Psychiatric Association. Use of this trademark does not constitute endorsement of this product by the American Psychiatric Association.
