(119) Establishing and Characterising Large COVID-19 Cohorts After Mapping the Information System for Research in Primary Care (SIDIAP) in Catalonia to the OMOP Common Data Model

Publication Number: 456

Background: Real-world data has proven to be a powerful resource in aiding the COVID-19 pandemic response. In this context, Common Data Models (CDM) are essential to efficiently perform international studies, which can generate meaningful and timely insights into COVID-19.

Objectives: The primary aim of this work was to convert the Information System for Research in Primary Care (SIDIAP), a database of population-wide primary care electronic health records from Catalonia, Spain, to the Observational Medical Outcomes Partnership (OMOP) CDM. Our second aim was to describe COVID-19-related outcomes among the general population of SIDIAP.

Methods: We mapped patient-level data from SIDIAP (including its linkage to hospital database) to the OMOP CDM. We performed more than 3,400 data quality checks to assess the readiness of the database for research. Subsequently, we established a general population cohort including all individuals registered in SIDIAP as of the 1 st March 2020. We identified outpatient COVID-19 diagnoses or positive test results for SARS-CoV-2, hospitalisations with COVID-19, COVID-19-related deaths, and first-dose vaccinations against COVID-19 until 30th June 2022.

Results: We mapped the SIDIAP database to the OMOP CDM and we verified the high quality of the transformed dataset (98.7% of the checks passed). We included 5,923,762 individuals in the general population cohort as of 1 st March 2020. Of those, 2,279,939 had either an outpatient COVID-19 diagnosis or positive test result, 95,018 had a hospitalisation with COVID-19, 12,340 had an ICU admission with COVID-19, 17,678 had a COVID-19 death, and 4,584,515 received a first-dose of a vaccine against COVID-19. People who were hospitalised or died were more commonly older, male, and with more comorbidities than those in the general population. Those admitted to ICU with COVID-19 were generally younger and more often male than those hospitalised and those who died. Vaccine recipients were typically younger than those admitted to hospital and those with a COVID-19 death.

Conclusions: We successfully harmonised SIDIAP to the OMOP CDM, and we illustrated its potential to perform COVID-19 research, as it captures COVID-19 diagnoses, test results, hospitalisations, deaths, and vaccinations in Catalonia, Spain. Extensive data checks have shown the data to be fit for use. The transformed SIDIAP database provides the basis for distributed network research related to the COVID-19 pandemic, and has already informed wide-ranging studies in COVID-19 and beyond.