Hi,
I'm using the function to perform univariate analysis. I got two very different beta estimations based on two different ways of specifying the covariate of the data.
In my example, my data=dats and the covariate of interest=age_dx_cat
First way, the covariate was specified using Surv()~dats[["age_dx_cat"]], data=dats, maxit=100. The result showed the significant association comparing age_dx_cat 15+ vs the reference group (see picture below)
In the second way, the covariate was specified using a standard approach, Surv()~age_dx_cat,data=dats,maxit=100. The result showed completely different beta estimation and insignificant association.
I have tried the two specifications of covariate using coxph() and the results were identical.
Hi, I'm using the function to perform univariate analysis. I got two very different beta estimations based on two different ways of specifying the covariate of the data.
In my example, my data=dats and the covariate of interest=age_dx_cat
First way, the covariate was specified using Surv()~dats[["age_dx_cat"]], data=dats, maxit=100. The result showed the significant association comparing age_dx_cat 15+ vs the reference group (see picture below)
In the second way, the covariate was specified using a standard approach, Surv()~age_dx_cat,data=dats,maxit=100. The result showed completely different beta estimation and insignificant association.
I have tried the two specifications of covariate using coxph() and the results were identical.
Sincerely, Joanne