Trendy! How do we know whether improvement has worked?

The trigger


We have recently tried to strengthen community hospitals to deliver more care locally with the hope to increase turn over and release pressure on secondary care beds. One day we are sitting in a meeting and everybody is rubbing their chins because there is activity data from the community hospitals – the number of patients seen and their length of stay, but it is a squiggly line – it is going up and down a lot. How do we know whether a) the number of patients seen has increased and b) the length of stay is getting better?


The problem


First a small secret: just measuring before and after a change is often not a good idea; the numbers always vary from day to day, week to week or month to month, if you plot them the resulting graph goes up-and-down and all over the place. We need to find a way to work out whether the up-and-down has an actual trend and that trend goes in the right direction.


Part of the solution


To analyse whether there is change in the data you can use a run-chart. If the data is in an Excel or csv format it can be copied into a spreadsheet: For a run-chart you need 15 data points – they could be days, weeks of months, but should be similar i.e. compare Mondays with Mondays, or week and weeks, but not Mondays with Sundays. In a 5 easy steps:

· Put the data into a graph.

· Calculate the median and add it to the graph.

· In a good chart the line will cross the median a few times. If it doesn’t you might need a bit of extra help.

· Look for 6 or more points that are on one side of the median – that is a shift: something has happened. 5 points on one side is good: it is a trend!

· If there is no run: Sorry - nothing happened, you have not achieved change yet.


Here is a quick read-up from our Scottish colleagues. http://www.knowledge.scot.nhs.uk/media/CLT/ResourceUploads/1006891/Good_Practice_Guide_Data_Management_run_chart_rules.pdf

and here a spreadsheet that will build run-charts automatically for you. http://webcache.googleusercontent.com/search?q=cache:77BFIjgjDuwJ:www.ihi.org/education/ihiopenschool/Courses/documents/practicumdocuments/run%2520chart%2520template.xls+&cd=4&hl=en&ct=clnk&gl=uk

P.S. Sorry: The activity in the community hospitals has not gone up (yet)!


Chris Subbe Consultant Physician Ysbyty Gwynedd



68 views0 comments

Recent Posts

See All