Fig. 5: Meta-regression of primary series vaccine effectiveness against severe COVID-19 by variant context and income status.
From: Global disparities in the introduction, scale-up, and effectiveness evaluation of COVID-19 vaccines
The squares and error bars indicate meta-analytical pooled estimates of vaccine effectiveness for each GNI quartile with 95% confidence intervals. Open squares indicate estimates in which there were 1–2 countries/territories represented for a given quartile. Each point represents an individual vaccine effectiveness estimate. Point size is proportional to study weight on an inverse variance scale, such that smaller points reflect smaller weights in the meta-regression. GNI quartile was included as a moderator in meta-analytic models, while country/territory was included as a random effect to account for the anticipated clustering of estimates at country/territory level. The absence of data for GNI quartile 1 for all but one comparison reflects the absence of estimates for this quartile that met the meta-regression inclusion criteria. The number of VE estimates is displayed to the right-hand side of each plot. GNI per capita Gross National Income.
