Report

QuEST Mental Health Data for Improvement Network SPC Charts Alison Redpath Senior Information Analyst Statistical Process Control (SPC) Run Chart vs SPC Run Chart SPC Displays data as a picture that shows variation over time Simple rules make it easy to spot and interpret patterns (and not over interpret) Shows signals of change Is more sensitive and shows special causes of variation Enables you to see the individual data points and the average at the same time Shows the natural range, useful in planning Needs small amount of data Need 20-30 data points as a minimum One way to create Many different types exist Which chart? Continuous Discrete What type of data? How many observations per subgroup? No Can both occurrences and non-occurrences be counted? Yes Are there equal areas of opportunity? 2-10 1 XbarR chart >10 XbarS chart XmR chart Yes c-chart No u-chart Are the subgroups equal size? No p-chart Yes np-chart Which chart? Measure Count What type of data? How many are represented by one data point? No Do we have both pass/fail, yes/no? Yes Is the chance the same for each point? 2-10 1 Yes >10 XbarR chart No XmR chart XbarS chart c-chart u-chart Do all data points represent the same number? No p-chart Yes np-chart Mental Health likely charts • • • • • • • • • Waiting times breachers per month % p-chart DNA % - p-chart New:follow-up ratio per month p-chart Number of referrals per month c-chart Number of patients on the caseload per month c-chart Total waiting list size c-chart Average waiting time per month XbarR chart Average waiting time per day XbarS chart Waiting time per patient XmR chart Method Equations https://www.moresteam.com/toolbox/statistical-process-control-spc.cfm Theory Rules for interpretation • • • • • Any point outside the control limits 2/3 points in the outer third 15 consecutive points in the inner third 8 or more above or below the average 6 or more in a trend Example • Number of Adult Psychiatry Appointments DNA'd in NHS Somewhere between January 2011 and January 2013 Example Further information • http://en.wikipedia.org/wiki/Control_chart has a list of different control chart types, with links to how to construct each of them • Register with IHI.org and then find the webex On Demand: Using Run and Control Charts to Understand Variation Further support Alison Redpath Senior Information Analyst QuEST Mental Health 01312443284 [email protected]