data visualization

Using ggplot2 to create Treatment Timelines with Multiple Variables

This post walks through code to create a timeline in R using ggplot2. These types of plots can help visualize treatment or measurement patterns, time-varying covariates, outcomes, and loss to follow-up in longitudinal data settings. Skip the step-by-step, just the code, please! Background Treatment timelines, or “swimmer plots”, are a visualization technique I find useful in exploring longitudinal data structures. A few years ago I shared how I make treatment timelines for a single treatment (categorical or continuous) in the post Patient Treatment Timelines for Longitudinal Survival Data.

Customizable correlation plots in R

TL;DR If you’re ever felt limited by correlogram packages in R, this post will show you how to write your own function to tidy the many correlations into a ggplot2-friendly form for plotting. By the end, you will be able to run one function to get a tidied data frame of correlations: formatted_cors(mtcars) %>% head() %>% kable() measure1 measure2 r n p sig_p p_if_sig r_if_sig mpg mpg 1.

Patient Treatment Timelines for Longitudinal Survival Data

I am a biostatistician at a research university, and I often find myself working with longitudinal survival data. As with any data analysis, I need to examine the quality of my data before deciding which statistical methods to implement. This post contains reproducible examples for how I prefer to visually explore survival data containing longitudinal exposures or covariates. I create a “treatment timeline” for each patient, and the end product looks something like this: