Outcome and follow-up time definitions.
infection
INFECTION, SARS-COV-2 INFECTION
The presence of a SARS-CoV-2 infection was defined as a participant-reported positive test result and/or seroconversion, which in turn was defined as anti-S1 seropositivity at the end of period 1 or anti-S1 and anti-N seropositivity at the end of period 2 (Episode duration and severity were based on the diary app data (The number of follow-up days was calculated as the number of days between vaccination and the first infection episode (the positive test date or the start date of the symptomatic period if no test date was available; for survival analyses) or the end of study (the month 12 sampling date or the last day of app completion if the participant did not provide a month 12 sample; for all other analyses). The app completion percentage was calculated for the period between vaccination and 27 March 2021 (