Describing agreement in the main condition coding field using Canadian ICD-11 inpatient data

Area of Science:

• Health Informatics
• Medical Record Analysis
• Data Comparability Standards

Background:

• International health data comparability is hindered by varying coding standards.
• The 'main condition' (MC) in discharge abstracts is coded as either 'reason for admission' or 'largest resource use'.

Purpose of the Study:

• To analyze the frequency of agreement in main condition (MC) definitions.
• To identify factors contributing to MC definition agreement in Canadian inpatient data.

Main Methods:

• Six coders reviewed 3,000 inpatient charts from Calgary acute care hospitals (August 2016-June 2017).
• MC was classified as 'reason for admission', 'largest resource use', or 'both'.
• Agreement was stratified by length of stay, admission source, demographics, and comorbidities; chi-square analysis was used.

Main Results:

• Only 1.51% of 2,250 charts showed disagreeing MC definitions.
• Agreement was associated with age, emergency admission, length of stay, hospital, and discharge location.
• Chronic conditions were more frequent in agreements; acute conditions were more frequent in disagreements.

Conclusions:

• A small proportion of cases had differing main conditions (MC) and largest resource use.
• Further research with larger sample sizes is needed to explore MC disagreements, patient complexity, and condition types.