Data

Firstly, we create an exemple data.

# Create example data
set.seed(923874)                
data <- data.frame(visit = rep(1:10, each=2),
                   value = round(runif(20, 10, 20),2),
                   lower = round(runif(20, 0, 10),2),
                   upper = round(runif(20, 20, 30),2),
                   n = sample(5:10, size=20, replace=T),
                   group = rep(c('A', 'B'), 10))

Interval plot using `ggplot2` package

Here, we will be using the geom_point() function to plot the points on the ggplot and then will be using the geom_errorbar() function with it to get the confidence intervals to the plot. We created a dotplot with confidence intervals with the below code.

library(ggplot2)

min_y <- floor(min(data$lower[data$group=='A'],na.rm=T))
max_y <- ceiling(max(data$upper[data$group=='A'],na.rm=T))

figure <- ggplot(data[data$group=='A',], aes(visit, value)) +
  geom_point(color="#0099B4FF") +
  geom_line(size=0.5, color="#0099B4FF") +
  geom_errorbar(aes(ymin = lower, ymax = upper), size=0.5, width=0.3, color="#0099B4FF") +
  labs(x = "Time (months)") +
  scale_x_continuous(breaks = seq(0, max(data$visit), 1)) +
  scale_y_continuous(breaks = seq(min_y, max_y, 5), limits = c(min_y, max_y)) +
  scale_color_manual(values=c("#69b3a2", "#404080")) +
  theme_classic() +
  theme(axis.title = element_text(size=9),
        legend.position = "top")

table <- ggplot(data[data$group=='A',], aes(x = visit, y = factor(1), label = n)) +
  geom_text(cex=3) +
  theme(
    panel.grid.major = element_blank(), 
    plot.background = element_blank(), 
    panel.grid.minor = element_blank(),
    panel.border = element_blank(),
    legend.position = "none",
    axis.line = element_blank(),
    axis.text.x = element_blank(),
    axis.text.y = element_blank(),
    axis.ticks = element_blank(),
    axis.ticks.x = element_blank(),  
    axis.title.x = element_blank(),
    axis.title.y = element_text(size = 10),
    plot.title = element_blank(), 
    panel.background = element_rect("white")
  ) + 
  scale_x_continuous(breaks = seq(0, max(data$visit), 1),
                     expand = c(0.07,-0.07)) +
  scale_y_discrete(name = "Number \n of patients")

ggpubr::ggarrange(figure, table, nrow=2, heights=c(0.8, 0.15), align = "v")

We add a parameter so see dotplot for group A and B simultaneously.

min_y <- floor(min(data$lower,na.rm=T))
max_y <- ceiling(max(data$upper,na.rm=T))

figure <- ggplot(data, aes(visit, value, col=group)) +
  geom_point() +
  geom_line(size=0.5) +
  geom_errorbar(aes(ymin = lower, ymax = upper), size=0.5, width=0.3) +
  labs(x = "", col="Arm") +
  scale_x_continuous(breaks = seq(1, max(data$visit), 1),
                     labels = paste("Visit",1:10)) +
  scale_y_continuous(breaks = seq(min_y, max_y, 5), limits = c(min_y, max_y)) +
  scale_color_manual(values=c("#69b3a2", "#404080")) +
  theme_classic() +
  theme(axis.title = element_text(size=9),
        legend.position = "top")

# reverse the order of the labels to get the right order in the table :
data$group_rev <- factor(data$group, levels=c('B','A'))
table <- ggplot(data, aes(x = visit, y = group_rev, label = n)) +
  geom_text(cex=3, check_overlap = TRUE) +
  theme(
    panel.grid.major = element_blank(), 
    plot.background = element_blank(), 
    panel.grid.minor = element_blank(),
    panel.border = element_blank(),
    legend.position = "none",
    axis.line = element_blank(),
    axis.text.x = element_blank(),
    axis.ticks = element_blank(),
    axis.ticks.x = element_blank(),  
    axis.title.x = element_blank(),
    axis.title.y = element_text(size = 10),
    plot.title = element_blank(), 
    panel.background = element_rect("white")
  ) + 
  scale_x_continuous(breaks = seq(1, max(data$visit), 1),
                     labels = paste("Visit",1:10),
                     expand = c(0.07,-0.07)) +
  scale_y_discrete(name = "Number \n of patients")

ggpubr::ggarrange(figure, table, nrow=2, heights=c(0.8, 0.15), align = "v")

Basic interval plot using `plotrix` package

This example explains how to use the plotrix package to draw a confidence interval plot.

library(plotrix)

plotCI(x = data$visit[data$group=='A'],              
       y = data$value[data$group=='A'],
       li = data$lower[data$group=='A'],
       ui = data$upper[data$group=='A'])

Interval Plot

Data

Interval plot using `ggplot2` package

Basic interval plot using `plotrix` package

Contact

Data

Interval plot using ggplot2 package

Basic interval plot using plotrix package

Contact

Interval plot using `ggplot2` package

Basic interval plot using `plotrix` package