Hospital Standardised Mortality Ratio (HSMR)
The majority of deaths that occur in hospital
are inevitable because of the patients’ conditions on admission.
However, some deaths can be prevented by improving care and
treatment or by reducing healthcare related harm.
An aim of the Scottish
Patient Safety Programme is to reduce hospital by 20% by
In order to monitor progress in relation to this
aim, the Information Services Division was asked to develop the
Hospital Standardised Mortality Ratio for Scottish hospitals. Since
December 2009, Public Health & Intelligence has published,
quarterly, HSMRs for all acute hospitals participating in the
Scottish Patient Safety Programme.
Healthcare Improvement Scotland and Public
Health & Intelligence systematically review the latest HSMR
figures each quarter.
The Scottish HSMR uses the routine linkage of
data obtained from hospital discharge summaries to death
registrations, the latter held by the National Records of Scotland.
The HSMR is a measurement tool where crude mortality data are
adjusted to take account of some of the factors known to affect the
underlying risk of death. The HSMR is calculated as the ratio of
the actual number of deaths within 30 days of admission to hospital
(irrespective of place of death) to the predicted number of deaths:
HSMR = observed deaths/predicted deaths. Further details of how the
Scottish HSMR is produced are available from the website of
Health & Intelligence
In 2011, Healthcare Improvement Scotland
produced a guide for NHS boards on using the HSMR.
In 2014 we lead a short life working group to
make recommendations on the Hospital Standardised Mortality
Ratio (HSMR) in Scotland.