COVID identification in primary care - probable covid - positive test

Coding system
CTV3 (Read V3)
Codelist ID


Codes indicating COVID-19 case (1 of 13 possible types of CTV3 codes that contain information related to COVID-19)


Search of TPP CTV3 codes for terms relating to coronavirus, with additional (manual) check for any missing terms against the SNOMED list of COVID-19 related codes.

Classification as "case" was then performed following review of terms by six OpenSAFELY team members (including epidemiologists, clinicians, statisticians and infectious disease modellers).


Signed off by

  • Krishnan Bhaskaran, LSHTM (July 16, 2020)
  • Laurie Tomlinson, LSHTM (July 16, 2020)
CTV3ID CTV3PreferredTermDesc CTV3Source
XaLTE Coronavirus nucleic acid detection
Y20d1 SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) RNA (ribonucleic acid) detection result positive
Y213a Antigen of 2019-nCoV (novel coronavirus)
Y228d Coronavirus disease 19 caused by severe acute respiratory syndrome coronavirus 2 confirmed by laboratory test (situation)
Y23f7 SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) detection result positive
Y240b SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) RNA (ribonucleic acid) qualitative existence in specimen

Codes not in the full codelist are in faint grey.