I need to calculate the prevalence ratios to show the trend of prevalence of a drug group used by pregnant women over the years (2001-2018). I would like to use the year 2001 with age distribution of pregnant women in 2001 as reference for following years.
Please show me how to calculate the standardized Prevalence ratio (95%CI) with SPSS (I am not familiar with other software).
The outcome (dependent) variable Drug group use (y/n).
Other variables: age at delivery of pregnant women (continuous, but can be re-coded into age groups), years of birth (2001-2018), date of the prescription of the drug group.
I tried to use GEE (generalized estimating equation), but I do not know which model to use: poisson, negative binomial or binary logistic?
GEE: because there are women deliver several times during 2001-2018
Please help me.