NHS Iconography Options

The NHS has developed variation and assurance icons that can be displayed in the SPC chart. For further information on what these icons mean, see the Plot The Dots documentation.

These settings adjust the display and formatting of these icons.

The variation icons summarise the points flagged by the patterns turned on in Outlier Settings; with no patterns turned on, they always show common cause. By default only the patterns at the last point are considered (Flag Only Last Point); turning it off considers every point. More than one icon shows when patterns in both directions are found.

The assurance icon compares the Additional Target Value with the last point’s three-sigma limits. It needs Show Alt. Target Line turned on in Line Settings, and an Improvement Direction of Increase or Decrease in Outlier Settings. Run charts show no assurance icon.

All Settings

NHS Icons Settings

Setting	Description	Default	Values
Show Variation Icons	Draws the NHS variation icons for the flagged points, or adds them as a summary table column.	Off	On or Off
Flag Only Last Point	Bases the variation icons on the last point only; off uses every point.	On	On or Off
Variation Icon Locations	Corner of the chart for the variation icons.	Top Right	• Top Right • Bottom Right • Top Left • Bottom Left
Scale Variation Icon Size	Multiplies the size of the variation icons.	1	Number, at least 0
Show Assurance Icons	Draws the NHS assurance icon, comparing the alt. target with the last point’s three-sigma limits. Needs the alt. target line and an increase or decrease improvement direction.	Off	On or Off
Assurance Icon Locations	Corner of the chart for the assurance icon.	Top Right	• Top Right • Bottom Right • Top Left • Bottom Left
Scale Assurance Icon Size	Multiplies the size of the assurance icon.	1	Number, at least 0