COVID-19 vaccination effectiveness rates by week and sources of bias: a retrospective cohort study.

ABSTRACT:

Objective

To examine COVID-19 vaccine effectiveness over six 7-day intervals after the first dose and assess underlying bias in observational data.

Design and setting

Retrospective cohort study using Columbia University Irving Medical Center data linked to state and city immunisation registries.

Outcomes and measures

We used large-scale propensity score matching with up to 54 987 covariates, fitted Cox proportional hazards models and constructed Kaplan-Meier plots for two main outcomes (COVID-19 infection and COVID-19-associated hospitalisation). We conducted manual chart review of cases in week 1 in both groups along with a set of secondary analyses for other index date, outcome and population choices.

Results

The study included 179 666 patients. We observed i

SUBMITTER: Ostropolets A 

PROVIDER: S-EPMC9402447 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature