key: cord-0994968-b0w5mk6j
authors: Linkins, Lori-Ann; Iorio, Alfonso; Little, Julian; Lavis, John
title: Extended Reporting Guidance for Vaccine Effectiveness Studies for Variants of Concern for COVID-19
date: 2022-04-07
journal: Vaccine
DOI: 10.1016/j.vaccine.2022.04.005
sha: ca2d740608031a02fd75c55a63a510d7f154a151
doc_id: 994968
cord_uid: b0w5mk6j

nan

Lori-Ann Linkins a , Alfonso Iorio Following the initial series of phase III RCTs showing vaccine efficacy against SARS-CoV-2, an increasing number of observational studies evaluating vaccine effectiveness have been published. While recognizing that all observational studies are subject to bias, the data from these studies provide valuable insight into the effectiveness of vaccines in the real world. Unfortunately, large variability in reporting results for vaccine effectiveness studies has made it difficult to pool results, and this problem has only worsened as the variants of concern have emerged.

WHO proposed an adapted STROBE checklist in their publication providing interim guidance on evaluation of post-COVID vaccine effectiveness reports [1]. This checklist recommended COVID-19 vaccine specific elements that should be included in reporting vaccine effectiveness studies. As authors of the ongoing 'Living Evidence Synthesis for Efficacy and Effectiveness of COVID-19 Vaccines for Variants of Concern' posted on the COVID-END website bi-weekly, we have reviewed hundreds of these studies since April 2021, and based on our experience, we propose additional points that could help strengthen the reporting of observational VE studies for COVID-19.

STROBE Item no. Report results for participants who were within the nonimmune period (e.g. 0 to 14 days of the first dose) separately. Do not include them with unvaccinated participants. Report results for people with prior infection separately or include prior infection as a covariate. Other analyses 17 Report vaccine effectiveness adjusted for prognostic factors for COVID infection, severity of disease, and vaccination, including age, sex, gender, race, ethnicity, socioeconomic factors, occupation/exposure risk (health care worker, long-term care) and chronic medical conditions or state adjustment for specified variables made no difference, and provide details on method of adjustment.

The COVID-19 Evidence Network to support Decision-making (COVID-END) is supported by funding from the Government of Canada through the Canadian Institutes of Health Research (CIHR). To help Canadian decision-makers as they respond to unprecedented challenges related to the COVID-19 pandemic, COVID-END in Canada is coordinating rapid evidence responses such as the one on vaccine effectiveness for variants of concern which led us to propose these points for consideration. The opinions, results, and conclusions are those of the evidence-synthesis team that prepared the rapid response, and are independent of the Government of Canada and CIHR. No endorsement by the Government of Canada or CIHR is intended or should be inferred.

Evaluation of post-introduction COVID-19 vaccine effectiveness: summary of interim guidance of the World Health Organization

☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work

☐ The authors declare the following financial interests/personal relationships which may be considered as potential competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.