How does the mapped ICD data in an EHR system compare to the hospital DAD data in Alberta, Canada?

Coding by human coders is burdensome to healthcare systems requiring advanced computerized techniques. Epic has collaborated with Intelligent Medical Objects (IMO) solution to integrate a solution where the clinical interface terminology is mapped to the International Classification of Diseases (ICD). This study assesses the agreement between the solution mapped ICD-10-CA codes in Alberta, Canada's EHR system (based on Epic) to the human coded ICD-10-CA codes in hospital Discharge Abstract Database (DAD).

In this retrospective analysis conducted in Alberta, Canada, we linked records in the acute care hospital DAD with the province wide EHR system for admissions between April 2021 and March 2024.

The primary outcome was the level of agreement between the solution mapped ICD-10-CA codes from the 'hospital problem list' in the EHR and hospital DAD data. The analysis was conducted at 3-digit and 4-digit ICD code level for main diagnosis and any diagnosis, and further stratified by physician specialty, hospital type and location, and length-of-stay.

A total of 603,437 unique hospital records were linked between hospital DAD and EHR. The average level of agreement at 3-digit level of ICD-10-CA code for main diagnosis was 47.5% and any diagnosis was 37.0%. The average number of diagnoses coded by human coders in hospital DAD was higher than the solution mapped data in EHR. The agreement varied by specialty and length-of-stay with specialties with more complex patients and longer stays showing the lowest levels of agreement.

Level of agreement between solution mapped EHR and hospital DAD for ICD-10-CA data was low, indicating significant differences between terminology mappings and the coding process.