Based on successes in other fields of medicine such as cardiac surgery, we have previously published our experience of developing similar cumulative sum (CUSUM) techniques for prospective outcome monitoring.1 Herein we present a Microsoft Excel Spreadsheet template that will undertake the relevant calculations and reporting using standard and simple data entry fields. This presents a simple tool that allows the potential for scalability of implementation from single units to regions or nationally.
The tool is free to use for non-profit purposes and can be downloaded by clicking on the link below, and future-proofing has been built in so that incremental versions of the CUSUM will always be available from this link.
Real-time monitoring of mortality in burns units has the potential to immediately mark when mortality rates are significantly higher or lower than predicted. Rapid feedback from targeted internal or external audit allows early intervention, to reinforce positive practice, and improve systems where outcomes could be unsatisfactory. It acts as an early warning trigger, to stimulate rigorous assessment of cases and give immediate feedback, so potentially preventing long runs of higher than predicted mortality. It also presents the opportunity to pick up on periods of excellence. A key consideration in designing any CUSUM tool is where to set the audit triggers. Setting the trigger point arbitrarily low will pick up all changes in outcome early, however at the risk of causing a significant number of false positive triggers.
Our unit uses a trigger of 2 excess survivors or deaths in adults and one excess death or survivor in children. Our goal is the early recognition of altered trends in mortality, with immediate internal audit. These figures are not therefore powered for the measurement of absolute mortality, or the comparison of units, but provide an internal “sense-check” to the day-to-day running of a busy burns unit. In our experience, this allows us to recognise and learn from changing trends in mortality before they become entrenched.
Please follow this link to download the latest version of the CUSUM Burns Excel spreadsheet: http://sbh.sagepub.com/site/CUSUMtemplate/CUSUMspreadsheet.xhtml
The spreadsheet contains all required instructions and incorporates reporting tools and graphs which are generated automatically as the data are input.
Footnotes
Disclaimer: The use of this tool comes with no warranty and users are advised to verify their own data and calculations.
Reference
- 1. Roberts G, Thorburn G, Collins D, et al. Development and implementation of prospective outcome monitoring in a regional burns service using cumulative sum (CUSUM) techniques. Burns 2013; 39(4): 571–576. [DOI] [PubMed] [Google Scholar]