Some people will do a pcr at 4,12 and 24 weeks post treatment if it is affordable and the doctor will allow it.
Being undetectable at the 12 week post pcr is about 95% percent predictive of svr (sustained viral response)
Being undetectable at 24 week (6 month) post pcr is about 99.5% predictive of svr
A 4 week post pcr will tell you if you have relapsed but I am not sure what the predictive value is, perhaps someone else knows.
If you can only do one of these do the 24 week pcr. As Will mentioned it is the is the most important.
Good luck and congrats on completing the course. At what week did you first become undetectable? Hopefully you had a pcr when you completed 4 weeks of treatment.
-Dave
Congratulations on ending treatment and the good result. A PCR at 6 mo. is the time frame to be cosidered SVR. If you happened to test positive(relapse) then a plan of action would have to be discussed with your doctor. Maybe don"t get ahead of yourself and for now just enjoy being finished with treatment and that you are UND.
Good luck
Will