Stacked cumulative percent plots

Abstract

Longitudinal data present analysts with the unique challenge of summarizing information over time without losing the detail of pattern changes, spikes, or other irregularities. This paper introduces a graphical method for displaying ordinal response trajectories that allows you to compare the percent response of multiple categories. As a result, researchers can not only detect symptom improvements or declines over time, but they can also visualize when the frequency of a category increased or decreased. The analyses and output discussed were created with Base SAS® Version 9.1 and SAS/GRAPH® software and will hopefully be of interest to SAS users of all skill levels.