I need to calculate the area under the curve (viral load over time) for
about 1000 study participants using the trapezoidal rule. I have used
aucdist but I am not getting a result and am not sure if I'm getting an
error message.
id = patient id
time = time of viral load test
conc = viral load value
aucdist id time conc, t generate(auc)
(t specifies that the integral be computed using the simple trapezoidal
rule, and generate(auc) specifies to create a new variable with the AUC (C
max, T max, log conc 0 -inf.))
but all I'm getting is (2000) in return which is supposed to mean that I
have no observations on which to perform the statistical operation.
I have 9500 observations with multiple observations per patient, there are
no missing data. Any suggestions as to what I may be doing wrong?
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