Reference health
A systematic review of effectiveness of BNT162b2 mRNA and ChAdOx1 adenoviral vector COVID-19 vaccines in the general population
6 of 26 checkable references need attention · checked 2026-07-25
At the dated check, the references listed below either did not resolve in Crossref or DataCite, or carried a retraction notice. Each one is shown with the registry record that put it there.
4 without a DOI — not checked. A reference deposited without a DOI is never matched by title or guessed at; it stays outside the checked set, and this line discloses that.
References needing attention
does not resolve to a known work10.1011/S0140-6736(21)00448-7
does not resolve to a known work10.1101/2021.5.22.21.257658
does not resolve to a known work10.1016//S0140-6736(21)00790-X
does not resolve to a known work10.1371/journal.pmed1000097
does not resolve to a known work10.1016/s0140-6734(21)00677-2
does not resolve to a known work10.1177/174074515597701
The 20 checked references that resolve
resolves10.1101/2021.03.01.21252652
Early effectiveness of COVID-19 vaccination with BNT162b2 mRNA vaccine and ChAdOx1 adenovirus vector vaccine on symptomatic disease, hospitalisations and mortality in older adults in England
resolves10.1101/2021.05.14.21257218
Effectiveness of BNT162b2 mRNA vaccine and ChAdOx1 adenovirus vector vaccine on mortality following COVID-19
resolves10.1101/2021.01.27.21250612
The effectiveness of the first dose of BNT162b2 vaccine in reducing SARS-CoV-2 infection 13-24 days after immunization: real-world evidence
resolves10.1038/s41390-021-01402-z
SARS-CoV-2 vaccine testing and trials in the pediatric population: biologic, ethical, research, and implementation challenges
resolves10.1056/NEJMoa2101765
BNT162b2 mRNA Covid-19 Vaccine in a Nationwide Mass Vaccination Setting
resolves10.1016/S0140-6736(21)00947-8
Impact and effectiveness of mRNA BNT162b2 vaccine against SARS-CoV-2 infections and COVID-19 cases, hospitalisations, and deaths following a nationwide vaccination campaign in Israel: an observational study using national surveillance data
resolves10.1101/2021.03.08.21252200
Vaccine effectiveness after 1
<sup>st</sup>
and 2
<sup>nd</sup>
dose of the BNT162b2 mRNA Covid-19 Vaccine in long-term care facility residents and healthcare workers – a Danish cohort study
resolves10.1101/2021.02.01.21250957
Estimating the effectiveness of the Pfizer COVID-19 BNT162b2 vaccine after a single dose. A reanalysis of a study of ‘real-world’ vaccination outcomes from Israel
resolves10.1038/s41541-021-00336-1
Comparative systematic review and meta-analysis of reactogenicity, immunogenicity and efficacy of vaccines against SARS-CoV-2
resolves10.1016/j.ijsu.2020.04.018
The socio-economic implications of the coronavirus pandemic (COVID-19): A review
resolves10.1038/s41591-021-01410-w
Impact of vaccination on new SARS-CoV-2 infections in the United Kingdom
resolves10.1177/2042098619865413
Postmarket surveillance: a review on key aspects and measures on the effective functioning in the context of the United Kingdom and Canada
resolves10.1016/S0140-6736(21)01358-1
SARS-CoV-2 Delta VOC in Scotland: demographics, risk of hospital admission, and vaccine effectiveness
resolves10.1101/2021.03.26.21254391
Vaccine effectiveness of the first dose of ChAdOx1 nCoV-19 and BNT162b2 against SARS-CoV-2 infection in residents of Long-Term Care Facilities (VIVALDI study)
resolves10.1016/S0140-6736(20)32661-1
Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK
The 4 references without a DOI — listed, not checked
no DOI — not checkedDepartment of health and social care. Statement from the UK Chief Medical Officers on the prioritisation of first doses of COVID-19 vaccines. https://www.gov.uk/government/news/statement-from-the-uk-chief-medical-officers-on-the-prioritisation-of-first-doses-of-covid-19-vaccines.
no DOI — not checkedHelfand BKI et al (2020) The exclusion of older persons from vaccine and treatment trials for COVID-19. J Am Med Assoc 180(11):1546–1549
no DOI — not checkedNational Heart, Lung, and Blood Institute. Study Quality Assessment Tools. https://www.nhlbi.nih.gov/. Accessed May 31, 2021.
no DOI — not checkedWorld Health Oganisation (WHO) WHO issues its first emergency validation for a COVID-19 vaccine and emphasizes need for equitable global service. https://www.who.int/home/news/. Accessed June 19, 2021a.
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checked 2026-07-25 — re-checked daily as this page is visited; titles and statuses come from Crossref and DataCite and are not part of the signed record
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