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Two Brains Are Better Than One: Smarter AI for Medical Term Mapping

Written by HiLabs R&D Team | Oct 9, 2025 2:43:33 PM

Unlocking the vast potential within unstructured clinical text is a primary goal for modern healthcare analytics. Because clinical data is messy, anyone who wants to unlock its value must start by cleaning & standardizing the data first and then mapping clinical terms to clean ontologies like SNOMED CT. While AI has made significant strides, the unique complexity of real-world clinical data remains a challenge, requiring new sophisticated approaches.

The Challenge: AI Models Underperform on Production Data

Benchmarks look great until they meet real charts. Academic datasets are pristine; production data isn’t. Real-world clinical charts are filled with abbreviations, typos, and contextual noise.

When that messy, real-world data hits general-purpose AI, the quality of output falls far short of what health plans require for operations. In our internal tests, a typical BERT-encoder pipeline—considered state-of-the-art based on benchmarks using academic datasets—managed about 60% accuracy on a real-world dataset. The gap isn’t cosmetic; it’s the difference between a system health plans can trust and one they quietly ignore.

The solution: a hybrid "Two-Brain" architecture.

Through our research, we developed and validated a new hybrid pipeline designed to handle the complexity of real-world clinical data. It mimics how a healthcare expert thinks, pairing deep semantic understanding with cross-method agreement.

  1. The Semantic Brain (The Expert): a powerful, deep learning model that functions as the "context expert." It performs a deep semantic analysis of the medical terms and each candidate to understand the clinical meaning, and it then produces a list of high-confidence candidates.
  2. The Consensus Brain (The Fact-Checker): an innovative algorithm that acts as a "second opinion." It analyzes the initial search results from multiple angles—lexical (looks similar) and semantic (means the same thing)—and asks a simple question: did different methods agree on the candidates? When multiple "opinions” points to the same conclusion, its score is boosted.

By combining these two signals, the system makes highly nuanced decisions. It weighs both the deep contextual relevance from the AI and the objective consensus from the initial search, resolving ambiguity with incredible precision.

The Two-Brain Approach in Action

While theory is important, performance on real-world clinical text is the true test. The examples below, drawn from our benchmark dataset, demonstrate how the hybrid AI pipeline handles diverse and challenging inputs —ranging from typos to shorthand to long-form natural language. For comparison, we also include outputs from a well-prompted, general-purpose large language model (LLM), such as Gemini 2.5 Pro. Although such models can approximate medical reasoning when prompted effectively, they lack domain-specific training and ontology awareness, often resulting in inconsistent or clinically imprecise mappings.

 

Clinical Data and AI: Generic LLMs vs Two-Brain, Healthcare-Trained Approac

Input Mention 

Generic LLM Prediction 

HiLabs Model Prediction 

Why the Two-Brain Approach Performs Better

hypordo ischemic encephalopathy 

Neonatal asphyxial encephalopathy (27747900) 

Ischemic encephalopathy (389100007) 

Better handling of complex spelling errors; avoids context hallucination (e.g., neonatal). 

Gdm 

Gestational diabetes (disorder) (11687002) 

Gestational diabetes mellitus (11687002) 

Ensures precise mapping to preferred clinical terms for consistency in analytics. 

Closed displaced spiral fracture of shaft of right tibia 

Fracture of tibia (disorder) (31978002) 

Closed fracture of shaft of right tibia (10925321000119100) 

Retains clinically relevant detail (e.g., location and type of fracture) without overgeneralizing. 

Persistent pain on the upper right portion of your abdomen 

Pain radiating to middle abdomen (427668002) 

Right sided abdominal pain (285388000) 

More accurate parsing of anatomical location; avoids incorrect inferences like "radiating." 

Elevated total protein 

Increased serum protein level / Hyperproteinemia (81711008) 

Serum total protein above reference level (1172922003) 

Selects the most precise SNOMED concept, minimizing ambiguity in downstream use. 

Post tussive emesis 

Post-tussive vomiting (disorder) (424580008) 

Post-tussive vomiting (424580008) 

Maintains high reliability across less common but clinically relevant terminology. 

Xr ankle left 

X-ray of ankle (procedure) 363680008 

Plain x-ray of left ankle (426420006) 

Uses domain-specific knowledge to accurately handle abbreviations and link procedural terms to SNOMED codes. 

The Results: Jumping from 60% to 89% Accuracy

To validate this hybrid approach, we ran a series of rigorous experiments on a ground-truth dataset of over 1,800 real-world medical terms from clinical charts. The results were transformative. By implementing this two-brain hybrid model, we were able to lift the baseline accuracy from the 60% achieved by standard AI models to 85% on the initial pass.

Further analysis of the remaining errors revealed a clear path forward. By implementing targeted, low-effort solutions for known challenges like clinical abbreviations and data indexing, the model was able to achieve a repeatable accuracy of ~89%. This represents a nearly 30-point improvement over other state-of-the-art solutions on the same noisy, real-world data.

 

The Future is Robust AI

In healthcare, performance on messy, real-world text is the real test—not on academic datasets that only exist in in researcher’s dreams. The next wave of healthcare data systems will be intelligent and multifaceted, built for this reality from day one. Our hybrid approach—combining deep semantic understanding with data-driven consensus—offers a robust, reliable, production-ready path to automated term mapping.

At HiLabs, we are dedicated to solving the most complex challenges in healthcare data. To learn more about our research and our approach to building next-generation AI solutions, visit our website.