Hello. I want to see the relationship between an outcome variable dose measured six time on every subject.
interval time are unequally spaced: every subject has differente time points... example: subject n°1 has the second visit after 3 days and the third after 6 days and subject n°2 has the second visit after 8 days and the third after 2 ecc...
the dataset is like this
ID genotype_CYP2C9 eta sex date_1 dose_1 date_2 dose_2... date_6 dose_6
1 N/N 64 M 28/02/08 34 31/03/08 24 25/09/09 13
2 N/2 78 F 13/08/08 23 21/09/08 12 26/12/09 12
3 N/3 65 F ecc
4 N/N 68 M ecc
what model i have to use?
proc mixed? proc genmod?
Iwant to see if dose changes over time and if there is a relation between genotype CYP2C9 and the dose of medicine.