The Hospital Standard Mortality Ratio (HSMR) is an important measurement tool that provides hospitals with a starting point to assess their mortality trends, identify opportunities for improvement and track their progress.

Public reporting of the HSMR is calculated by the Canadian Institute for Health Information (CIHI) and the results are posted annually on their website.

The Formula for HSMR is equal to the number of observed deaths divided by the number of expected deaths, multiplied by 100.

Observed deaths: Number of deaths in a hospital
Expected deaths: Expected number of deaths based on overall mortality in the reference year (2004-2005)

The HSMR is adjusted for other factors affecting mortality such as age, sex, and length of stay in the hospital.

How to interpret the HSMR:

• An HSMR equal to 100 suggests that there is no difference between the hospital's mortality rate and the overall average rate.
• An HSMR greater than 100 suggests that the local mortality rate is higher than the overall average.
• An HSMR less than 100 suggests that the local mortality rate is lower than the overall average.

It is important to note that the HSMR is not designed for comparisons between hospitals; it is intended to track a hospital's trend over time.

Annual reports on HSMR, and the means used to calculate the rate are available from the CIHI Website.