Missing Occupation, Missing Risk: Insights From COVID-19 Case Investigation Data in Busan, South Korea

Area of Science:

• Public Health
• Epidemiology
• Occupational Health

Background:

• COVID-19 surveillance relies on accurate occupational data for risk assessment.
• Early surveillance in Busan (2020-2021) faced challenges with inconsistent occupational data integration.
• The importance of occupation for infection-risk assessment was recognized despite reporting inconsistencies.

Purpose of the Study:

• To evaluate the quality and analytic utility of occupational data in COVID-19 case investigations in Busan, South Korea.
• To assess the completeness, consistency, and codability of occupational information.
• To examine temporal trends and identify limitations in the collected occupational data.

Main Methods:

• Analysis of 25,283 confirmed COVID-19 cases from February 2020 to December 2021.
• Extraction of occupational data from investigation forms, epidemiological reports, and electronic medical records.
• Assessment of data completeness, internal consistency, and codability to the Korean Standard Classification of Occupations (KSCO).

Main Results:

• Occupational information was recorded for over 99% of cases, but entries were frequently vague or institutional, limiting utility.
• A small proportion of entries could be standardized to KSCO due to ambiguous wording or contradictions.
• Data collection for occupation ceased post-2021, with pre-existing design flaws limiting analytic value.

Conclusions:

• Busan's COVID-19 surveillance system captured occupation for most cases but yielded limited analyzable information.
• Data entry limitations highlight the need for structured coding, picklists, and quality checks for occupational risk assessment.
• Systematic identification of occupational risk is essential for future pandemic preparedness and response.