The relative risk in a cohort study with Poisson cases
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Inverse Probability of Treatment Weighting (Propensity Score) using the Military Health System Data Repository and National Death Index
Published on: January 8, 2020
1Institute of Biostatistics, Erasmus University, Rotterdam, The Netherlands.
Abstract:
This paper deals with making statistical inference about the relative risk (or risk ratio) in a cohort (or prospective) study with dichotomous exposure when the number of cases is a Poisson distributed variable. The exact procedure for testing the null hypothesis for the relative risk and the exact computation of its confidence interval for a single 2 X 2 table is presented. Maximum likelihood methods and the homogeneity test are presented for the common risk ratio when data is stratified in several 2 X 2 tables. These methods are based upon a sufficient statistic and therefore are considered proper statistical alternatives to the more descriptive epidemiological measures such as (in)directly standardized mortality (morbidity) ratios. All computations can be done on a programmable pocket calculator. With the HP-41 CV more than 70 strata can be distinguished.
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