Using SPC charts to provide assurance during COVID-19

The Health and Business Intelligence (HBI) Team at NHS Tayside worked with Data and Measurement Advisors at Healthcare Improvement Scotland (HIS) to create a template that would help support organisational decision making and provide information in a streamlined manner during COVID-19.

Statistical Process Control (SPC) Charts are a graphical tool commonly used in Quality Improvement (QI) work to monitor progress over time, and they provide services with an in-depth way to report data over time, highlighting whether changes in the data can be attributed to normal variation or a change within the service. By using baseline or historical data, you can then calculate the mean and the control limits across the data points. To learn more about SPC charts and how to build them, please see the available resources on the NES QI Zone.

Present data in a statistically sound way so it tells a story" NHS Tayside HBI Team Lead

During COVID-19, NHS Tayside wanted to create a new way of collating and reporting data at pace in a way that was easy to understand without requiring previous in-depth statistical knowledge and expertise. The team were tasked with presenting weekly Board Business Critical reports that included details such as admissions, performance data alongside targets, and waiting times. They had previous experience of using SPC charts and identified these may be more appropriate than the bar charts they were using, however wished to increase the functionality of their excel template in order to allow meaningful communication of patterns in their data. Seeking advice from HIS data and measurement advisors and after a practical ‘how to’ session, the team were able to tailor the template to best suit their needs.

The new template has the functionality to add annotations, set the mean and allows the team to show shifts in their data manually. The charts allow the team to describe a system in terms of different states, for example a pre-COVID-19 state, or a remobilisation state, and identify shifts away from those states, allowing services to better understand the influence that they and the wider system have on the measures. By adding colour coding and creating their own baseline based on fewer figures (with guidance from HIS), the team were able to confidently present meaningful data to the Board. 

       Image 1: Previous way of reporting outpatient and TTG demand

Image 2: The new way of reporting outpatient and TTG demand 

Using the HIS SPC template and guidance, allows the team to tell much more of story, making data easier to read and interpret.

The success of the chart’s easy to use format has led to the team expanding their use for reporting data even following the disbanding of the business critical group (who this work was initially for). They are now using this format when reporting to both the operational leadership and executive leadership teams, as well as to other services. By creating a data reporting template that is easy to interpret, members of the team have also been able to spread the learning and deliver training sessions, increasing the capabilities of others. They are also sharing the learning with improvement advisors.
The team have witnessed how reporting data in this way at meetings sparks discussions and has instigated further investigations and ‘deep diving’ with services who wish to understand what changes have resulted in the shifts shown in their data.

An example of the template in use is available for download.


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