Bringing Data to Life with Post-Hoc CUSUM Charts

  • G Robin Henderson
  • Ross Davies
  • Deborah Macdonald


In analyzing healthcare data and presenting the results to clinical and management colleagues the authors have found that both Shewart and CUSUM charts have been invaluable. In particular the post-hoc CUSUM chart is a useful tool for the detection of improvement in the level of performance of healthcare processes. The charts of the healthcare data displayed and discussed were created using the widely available statistical software package Minitab but information on how to create the charts using Microsoft Excel is included. The authors believe that this case study would be of value to classes in applied statistics at intermediate level in courses including an element on applications to process improvement.