Patient Improvement Measures

This information display shows you how this hospital compares to the national average for a range of measures used to demonstrate quality in joint replacement surgery. Against each measure you will be able to see whether this hospital is performing better than expected, within the expected range or worse than expected for this type of surgery. In some cases, favourable results are indicated by higher numbers and in some cases, by lower numbers. This depends on the type of measure displayed. However, all the thermometer charts have been designed to report better performance on the right hand side and poorer performance on the left hand side.

   The green banding represents the expected range of performance for hospitals.
   The grey dotted line represents the national average.
   The black marker represents the hospital you have selected. This marker shows where this hospital’s performance sits in relation to the expected range and the national average.
   Hover over the icon for a further definition of the quality measure and its source, including details about risk adjustment

Important note 1: These data are a snapshot in time of the relative performance of this hospital. A hospital’s results may fluctuate over time and get progressively better or worse, reflecting the types of procedures they carry out and/or the types of patients that they treat among other, local factors.

Important note 2: This thermometer chart has been created to aid interpretation of the patient improvement figures in the table (to the left of the thermometer). It is designed to show where Trusts perform better or worse than the national average and where their performance is within the expected range or outside the expected range. For any given result (whether better or poorer), it also shows how likely it is that their performance has varied because of ‘chance’ or because of actual practice. This depends on the how far the result is from the national average and the number of patients on which the analysis is based. The further the hospital indicator (black marker) is from the centre, the less likely this is to be down to chance, especially if a large number of patient records have been analysed for the hospital. Where the number of patient records is low, this might indicate a less certain result.

Important note 3: The green band represents the range over which any performance away from the national average is not thought to be significant. However, it also worth noting that there is a less than one in a five hundred chance that the results for any individual hospital could fall outside the expected range by chance alone

An example for (fictional) Trust A is shown below


The results for Trust A show that for patient reported health improvement, two measures show a slightly higher average health gain than the national average over the 12-month period. These results are within the expected range of performance for all three measures.

Click here to see the FAQ about hospitals showing ‘worse than expected’ results FAQs