The University of Southampton
University of Southampton Institutional Repository

Why do we continue to use standardized mortality ratios for small area comparisons?

Julious, S., Nicholl, J. and George, S. (2001) Why do we continue to use standardized mortality ratios for small area comparisons? Journal of Public Health Medicine, 23, (1), pp. 40-46.

Record type: Article


Public health practitioners are often faced with the necessity to compare the mortality experience of different geographical areas. Indirect standardization, producing a 'standardized mortality ratio' (SMR) is the most commonly used technique for doing this. However, as we show, indirect standardization is inappropriate for such comparisons, as SMRs for different geographical areas have different denominators. The fact that indirect standardization is usually chosen for this type of comparison is probably based on two beliefs: (1) that direct standardization yields only a rate rather than a more easily interpreted ratio or index; (2) that direct standardization cannot be carried out in many cases because the sub-group specific mortality rates in the groups to be compared are not available or, in at least some age classes, are based upon such small numbers as to be completely unreliable. In this paper we show that a simple index (the comparative mortality figure) can be calculated from the directly standardized rate in most cases. Using a comparison of the overall mortality experience of electoral wards in Sheffield between 1980 and 1987 we demonstrate also that the advantage gained by the smaller standard error of the SMR is outweighed by the bias inherent in its construction. We recommend that the SMR is used only when absolutely necessary, that is, in the rare circumstance when data are not available for the calculation of age- and sex-specific subgroup rates in the study population.

Full text not available from this repository.

More information

Published date: March 2001
Keywords: small area statistics, standardization


Local EPrints ID: 24354
ISSN: 0957-4832
PURE UUID: 91e3eaf2-413a-470a-b2ce-3f7079b4cf60

Catalogue record

Date deposited: 29 Mar 2006
Last modified: 17 Jul 2017 16:13

Export record


Author: S. Julious
Author: J. Nicholl
Author: S. George

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton:

ePrints Soton supports OAI 2.0 with a base URL of

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.