Standardized Mortality Ratio
The standardized mortality ratio (SMR) compares the number of deaths actually observed in a study population with the number that would be expected if that population had experienced a standard set of age-specific death rates. It is the central output of indirect standardization: a single ratio, usually multiplied by 100, that says whether a group's mortality is higher or lower than a reference after accounting for its age structure. Because it needs only the study group's age distribution and total deaths — not stable age-specific rates within the group — the SMR is the method of choice when the group is small or its age-specific deaths are sparse.
Read the full method
Sign in with a free account to read this section.
Method map
The neighbourhood of related methods — select a node to explore.
Sources
- Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell. ISBN: 9781557864512
- Breslow, N. E., & Day, N. E. (1987). Statistical Methods in Cancer Research, Volume II: The Design and Analysis of Cohort Studies. IARC Scientific Publications No. 82, Lyon. ISBN: 9789283201823
How to cite this page
ScholarGate. (2026, June 22). Standardized Mortality Ratio (SMR). ScholarGate. https://scholargate.app/en/demography/standardized-mortality-ratio
Which method?
Set this method beside its closest kin and read them side by side — the library lays the books on the table; the choice is yours.
- Direct StandardizationDemography↔ compare
- Indirect StandardizationDemography↔ compare
- Kitagawa DecompositionDemography↔ compare
- Life TableDemography↔ compare