Assurance Types

Assurance icons show how consistently a measure can be expected to meet the target set for it. There are three icons:

Icon	Definition
	Variation indicates inconsistently hitting, passing and falling short of the target. This means that the target may sometimes be met and sometimes missed due to random variation.
	Variation indicates consistently (P)assing the target.
	Variation indicates consistently (F)alling short of the target.

The visual compares the Additional Target Value with the last point’s three-sigma (99%) limits. A target between the limits gives the hit or miss icon (shown as Inconsistent in the summary table’s filter). A target beyond the limits gives a pass when the process sits on the favourable side of it, and a fail otherwise: for example, with an Improvement Direction of Increase, a target below the lower limit is a pass and a target above the upper limit is a fail.

The icon needs Show Alt. Target Line turned on in Line Settings and an Improvement Direction of Increase or Decrease; run charts show no assurance icon.

For more information on assurance icons, please see the NHS guide: Making data count - Strengthening your decisions.