Extended Data Fig. 2: A subgroup intention-to-treat analysis of the primary outcome of COVID-19 booster dose uptake among grandparents.
RR = risk ratio. CI = confidence interval. In the forest plot, the points are represented as the point estimate of risk ratio, and the lines are represented as the range of the 95% confidence interval. Model 1 is a Poisson regression model. Model 2 is a Poisson regression model with robust standard error. In the two models, adjustment is made for grandparents’ sex, age, residence, education, history of cohabitation with the enrolled grandchild, living status, frequency of leaving the home, and presence of one or more chronic disease. P value is from interaction tests using Model 2. Analyses are two-sided at 5% significance level.
