Hospital standardized mortality ratio: consequences of adjusting hospital mortality with indirect standardization.

Background: The hospital standardized mortality ratio (HSMR) is developed to evaluate and improve hospital quality. Different methods can be used to standardize the hospital mortality ratio. Our aim was to assess the validity and applicability of directly and indirectly standardized hospital mortality ratios.

[Variations in Dutch National Medical Registration hardly affect the hospital standardised mortality rate (HSMR)].

Objective: To analyse the variation in the registration of hospital admissions across Dutch hospitals and determine how this variation affects the Hospital Standardised Mortality Rate (HSMR).

Design: Retrospective, descriptive.

Method: We used data from the National Medical Registration (LMR), covering the records of all hospital admissions in 2005 in Dutch hospitals, to analyse the variation between hospitals in 3 variables: the number of secondary diagnoses, the percentage of unplanned admissions, and the percentage of non-specified diagnoses ('other diagnoses').

Measuring and explaining mortality in Dutch hospitals; the hospital standardized mortality rate between 2003 and 2005.

Background: Indicators of hospital quality, such as hospital standardized mortality ratios (HSMR), have been used increasingly to assess and improve hospital quality. Our aim has been to describe and explain variation in new HSMRs for the Netherlands.

Methods: HSMRs were estimated using data from the complete population of discharged patients during 2003 to 2005.