Stacked cumulative percent plots
Gilligan, T. (2009). Stacked cumulative percent plots. In Pharmaceutical Industry SAS Users Group Conference, Paper PR06-2009, PharmaSUG, Portland, OR, May 31-June 3, 2009,.
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.