What does it show?
Mortality results and funnel plot for all admitting teams based on a year’s data, plus information about how mortality results are derived.
We have adjusted case mix including stroke severity. The model used for this has been published in Stroke, and the published paper shows that the model is very reliable when externally validated. Briefly, the model takes account of the age of the patient, whether they are in atrial fibrillation (AF) before stroke, stroke type (haemorrhage or infarction), and the NIHSS score at arrival (where this is not available, the level of consciousness at arrival).
Data submitted to the Sentinel Stroke National Audit Programme (SSNAP) for patient admissions has been linked with data from the Office for National Statistics in order to determine all cause mortality for the patients with known stroke type you directly admitted to the audit between April 2016 and March 2017. The number of deaths recorded within 30 days of admission (or stroke onset if inpatient stroke) in either ONS or SSNAP for each team's patients was used to calculate the team's crude mortality percentage.
How can you use it?
Following analysis and case mix adjustment the expected number of deaths for each team's patients, and the Standardised Mortality Ratio was calculated. Each team’s SMR and the control limits are plotted on the funnel plot.
The funnel plot is useful for identifying outliers, taking into account the number of patients per team. What is therefore important is whether the point representing each team lies outside the dotted lines (the funnel). Points inside the funnel represent teams where the number of observed deaths is not significantly different to the number of expected deaths.
The funnel area of the plot becomes narrower as the number of expected deaths increases because the more patients there are, the less likely variations in the number of deaths are due to chance alone.
For those teams where the number of observed deaths is significantly higher than the number of expected deaths, their point on the funnel plot lies above the top dotted line. These teams are outliers at the 99.8% control limit and their SMR in the public table is higher than their upper 99.8% control limit.
You can find out more about outlier policy for SSNAP stroke mortality reporting here
Teams should use the mortality data to help better understand mortality in their patients and should consider carrying out case reviews to identify opportunities to improve the quality of care that stroke patients receive.
For more detailed information for SSNAP users on mortality reporting please see our mortality information sheet here.
Where can I find it?
The national mortality results are in the form of a public table. To view this table:
Mortality results for all teams are available here
- Results > Clinical audit > National and then click on the ‘Annual’ radio button:
We would greatly appreciate any feedback that you have on this report. If you found the report useful, or think there is any way that we could improve the report, we would love to hear from you. Please feel free to email via the contact button, or leave a comment below.