I am interested in assessing the viral load over time for HIV and hepatitis
C. I used -pkcollapse- in the past but since all patients have disease and
got it at some unknown time in the past, I had to create an artificial time
and concentration point of 0,0. -pkcollpase- was written with drug
concentrations in mind where a drug is given to someone at time 0 (and also
had no drug in the system and thus concentration was 0). In my case,
patients had disease for some unknown period of time so I don't have point
0,0. It was recommended to me in this listserve to create 0,0 by
subtracting the initial data from itself and subsequent points. This
worries me as I prefer to not "throw away" data. Has anyone used
-pkcollapse- in a similar circumstance or does this method sound reasonable
to them?
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