Study registration: *
Publication Lopez Bernal J, BMJ, 2021
Dates: 2020-10-26 to 2021-02-21
Funding: Public/non profit (There was no external funding for this study. Funded by Public Health England)
Conflict of interest: no COI (All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf and declare: funding from Public Health England for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years, no other relationships or activities that could appear to have influenced the submitted work.)

Methods

Study design:Test-negative
Description of participants: Adults aged 70 years and older who reported symptoms of COVID-19
Inclusion criteria:
  • Adults older than 70 (defined as those aged 70 and older on 31 March 2021)
  • reporting symptoms of COVID-19
  • RT-PCR test within 0-10 days of symptom onset

Exclusion criteria:
  • Previous positive PCR or antibody test result at any time before 8 December

Follow-up duration (months): 4
Vaccines:
  • 1 or 2 doses of ChAdOx1-S
  • 1 or 2 doses of BNT162b2
Variant description :
Variant name: Alpha
Evidence: Indirect evidence (prevalence of variant in the population: 98%-100%)
Documents
available

Protocol

NR

Statistical plan

NR

Data-sharing stated: NR
Data accessibility: Data sharing: No additional data available.
General comment Concerns mainly over uncontrolled confounding; in addition there are uncertainties over the possibility of selection bias in a test-negative design.