09-04-2023, 01:55 PM
An excerpt from Revista de Saúde Pública, Proportional cancer incidence according to selected sites … , v-25 i-3 1991, pg-192
" Appendix
Interpretation and calculation of the Standardized Proportionate Incidence Ratio (SPIR)
The SPIR for a selected site j informs how many times the observed total number of cases for this site is greater in the study population than would be expected if, for each age in the age range of interest, the ratio ''number of cases for site j / total of cases" were the same as the relation ''incidence rate for site j / incidence rate for all sites", the incidence rates being chosen from a reference population, also called the standard population.
Since the SPIR is not based in an underlying Poisson distribution, as the Standardized Mortality Ratio (SMR) is, the confidence intervals presented should be viewed as approximation ones.
…
Program for HP 11C pocket calculator "
see attachment
[attachment=12501]
BEST!
SlideRule
" Appendix
Interpretation and calculation of the Standardized Proportionate Incidence Ratio (SPIR)
The SPIR for a selected site j informs how many times the observed total number of cases for this site is greater in the study population than would be expected if, for each age in the age range of interest, the ratio ''number of cases for site j / total of cases" were the same as the relation ''incidence rate for site j / incidence rate for all sites", the incidence rates being chosen from a reference population, also called the standard population.
Since the SPIR is not based in an underlying Poisson distribution, as the Standardized Mortality Ratio (SMR) is, the confidence intervals presented should be viewed as approximation ones.
…
Program for HP 11C pocket calculator "
see attachment
[attachment=12501]
BEST!
SlideRule