Table 2.

Data extraction criteria and variables included

Classification		Contents
Data extraction criteria	COVID-19-related diseases1	B343, B927, Z208, Z290, U18, U181, Z038, Z115, U071, U072
	COVID-19-related treatment received2	RT-PCR, other COVID-19 related fee codes
Variables included	200 Table (summary information)	claim alternative key/patient alternative key/insurance type/gender/patient b-day/patient age_1/patient age_2/provide ID serial no./provider type/region code/healthcare service type/primary diagnosis code/secondary diagnosis code/medical department/service start date/service end date/first diagnosis date/no. of treatment days/no. of treatment & drug administration days/no. of days outpatient prescription/total drug expenditure of prescription/total no. of outpatient prescription cases/total treatment amount after review/co-payment amount/insure payment amount/100% co-payment amount/diagnosis with surgery/code of disease or injury related to official duties/code of disaster-related/specific code of injury by exogenous factors/patient status of discharge/patient’s route to the provider/type of medical aid/claim method type/claim type/month and year of review/medical department code indicated by provider/code of COVID-19 confirmed case/code of death by COVID-19 (39 variables)
	300 Table (treatment information)	claim alternative key/patient alternative key/code of category/code of classification type/code of classification/amount per single dose/amount per daily dose/total usage of day/total days of medication/number of total usage/unit price/medical fee/total amount after application of additional charge/code of generic drug name/exception classification code/additional charge code (16 variables)
	400 Table (diagnosis information)	claim alternative key/patient alternative key/serial no. of disease/code of disease/disease classification code/medical department/code of internal medicine subspecialty department (7 variables)
	530 Table (prescription information)	claim alternative key/patient alternative key/prescription issuance no./code of classification type/code of classification/single dose/number of administration per day/total days of medication/number of total usage/unit price/amount of prescribed drug/code of generic drug name (12 variables)

COVID-19, coronavirus disease 2019; RT-PCR, real time reverse transcription polymerase chain reaction.

¹Korean Standard Classification of Disease codes.

²Electronic Data Interchange codes.