Data
202,354 items of data are available, covering 201,658 participants, encoded using Data-Coding 
603.
Defined-instances run from 0 to 1, labelled using Instancing 
154.
 
2 Instances
Instance 0 : First COVID-19 antibody test taken, Feb 2021 to July 2021
201,658 participants, 201,658 items
Instance 1 : Repeat COVID-19 antibody test taken, March 2021 to July 2021
696 participants, 696 items
 
Notes
Participants self-reported the result of their COVID-19 antibody self-testing device, either by submitting it online via their UK Biobank participant account, using a paper questionnaire returned to UK Biobank in the mail or via phone to the UK Biobank Participant Resource Centre. Fortress kits from Phase 1 produced results that differentiated between IgG antibodies (long-term) and IgM antibodies (short-term). AbC-19
TM kits from Phase 2 provided test results for IgG antibodies only. 
 Resource 4500 and Resource 4501 describe Phases 1 and 2 of the coronavirus self-test antibody study.