Covid-19 Living Data

Study registration: *
Publication Skowronski DM, medRxiv, 2021
Dates: 2021-03-01 to 2021-10-02
Funding: Public/non profit (Provincial health authorities )
Conflict of interest: Yes (GDS received a grant paid to his institution for a meningococcal seroprevalence study from Pfizer in 2016. MK received grants/contracts paid to his institution from Roche, Hologic and Siemens, unrelated to this work. MS has been an investigator on projects, unrelated to the current work, funded by GlaxoSmithKline, Merck, Pfizer, Sanofi-Pasteur, Seqirus, Symvivo and VBI Vaccines. All funds have been paid to his institute, and he has not received any personal payments. RG received honoraria for an RSV Coordinators Workshop funded by AbbVie. Other authors have no conflicts of interest to disclose.)

Methods
Methods	Study design:Test-negative Description of participants: SARS-CoV-2 test-positive cases and test-negative controls 18 years and over residing in Quebec, Canada Inclusion criteria: Specimens with collection dates between weeks 22–39 (May 30 to October 2) Cases included any RT-PCR-confirmed SARS-CoV-2 infection Controls included all specimens that were RT-PCR-negative for SARS-CoV-2 and met inclusion/exclusion criteria. Exclusion criteria: Vaccinated 0-13 days prior Specimens with invalid or missing information were excluded as were specimens collected from individuals: identified as cases before the analysis period residents of LTCFs, assisted-living or independent-living facilities vaccinated with a single dose or product other than BNT162b2, mRNA-1273 or ChAdOx1 or when tested outside of the public-funding scheme owing to systematically lower likelihood of test-positivity. Follow-up duration (months): 7.2
Vaccines:	2 doses of BNT162b2 2 doses of mRNA-1273 2 doses of ChAdOx1-S 1 dose of BNT162b2 and 1 dose of mRNA-1273 1 dose of ChAdOx-1 and 1 dose of BNT162b2 or 1 dose of mRNA-1273
Variant description :
Variant description :	Variant name: Delta Evidence: Direct evidence (effectiveness determined by sequencing cases)
Documents available	Protocol NR Statistical plan No Data-sharing stated: Yes Data accessibility: Correspondence: D. M. Skowronski MD, FRCPC, 655 West 12th Ave, Vancouver, British Columbia, V5Z 4R4, Canada (danuta.skowronski@bccdc.ca).
General comment	The pre-print article and supplementary material were used in data extraction and risk of bias assessment. The study assessed SARS-CoV-2 infection and hospitalization vaccine effectiveness in Quebec (analysed here) and British Columbia (analysed separately) using a test-negative case control design adjusting for age, sex, week, and region. Concerns over uncontrolled confounding and the lack of a statistical analysis plan.