PT  - JOURNAL ARTICLE
AU  - Moura, Cristiano S.
AU  - Neville, Autumn
AU  - Liao, Fangming
AU  - Wen, Bijun
AU  - Razak, Fahad
AU  - Roberts, Surain
AU  - Verma, Amol A.
AU  - Bernatsky, Sasha
TI  - Validity of hospital diagnostic codes to identify SARS-CoV-2 infections in reference to polymerase chain reaction results: a descriptive study
AID  - 10.9778/cmajo.20230033
DP  - 2023 Sep 01
TA  - CMAJ Open
PG  - E982--E987
VI  - 11
IP  - 5
4099  - http://www.cmajopen.ca/content/11/5/E982.short
4100  - http://www.cmajopen.ca/content/11/5/E982.full
SO  - CMAJ2023 Sep 01; 11
AB  - Background: In 2020, International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) codes were created for laboratory-confirmed SARS-CoV-2 infections. We assessed the operating characteristics of ICD-10 discharge diagnostic code U07.1 within the General Medicine Inpatient Initiative (GEMINI).Methods: GEMINI assembles hospitalization data (including administrative ICD-10 discharge diagnostic codes, laboratory results and demographic data) from hospitals in Ontario, Canada. We studied adults (age ≥ 18 yr) admitted during 2020 and tested at least once for SARS-CoV-2 via polymerase chain reaction (PCR) during (or within 48 h before) hospitalization. With PCR results as the reference standard, we calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for ICD-10 code U07.1 hospital discharge diagnostic codes. Analyses were stratified by demographic data, calendar period and timing of the first test (within or after 48 h of hospital admission).Results: In 11 852 hospitalizations with at least 1 SARS-CoV-2 PCR test, 444 (3.7%) were positive. The sensitivity of code U07.1 to identify SARS-CoV-2 infection was 97.8%, specificity was 99.5%, PPV was 88.2% and NPV was 99.9%. Operating characteristics were similar in most stratified analyses, but the specificity and PPV were lower if the first SARS-CoV-2 test was done more than 48 hours after admission.Interpretation: The sensitivity, specificity, PPV and NPV of code U07.1 were high. This supports using code U07.1 to identify SARS-CoV-2 infection in hospitalization data.