Unable to obtain AUC

[jeslo328]

Please include a minimal reproducible example (AKA a reprex). If you've never heard of a reprex before, start by reading https://www.tidyverse.org/help/#reprex.

If you think that you have found a bug or you have a feature request, please briefly describe your problem and what output you expect.

If you have a question, please ask what you're curious about ideally with expected input, output, and what you have tried (a reprex, if feasible).

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Brief description of the problem
I am trying to get auc and also auc at certain interval eg 8hr,12hr for simulated data.
Unfortunately i am getting NA for the AUC. I am not sure what is going wrong.
Data attached and code as below:

simout4 <- dataset.list %>%
filter(TIME!=0 & EVID==0)

Calculate individual PK parameters

param <- simout4 %>%
group_by(DRUG, ID) %>%
arrange(DRUG, ID, as.numeric(TIME)) %>%
summarize(CMAX = max(IPRED),
CMIN = min(IPRED),
AUC6 = pk.calc.auc.last(DV,TIME, interval=c(0, 24)))

please advise

# insert reprex here

dataset.list.zip

[billdenney]

Thanks for sharing a reproducible example with your data. The following should work:

library(tidyverse)
library(PKNCA)

d_raw <- read_tsv("dataset.list.txt")

head(d_raw)

# Remove dosing rows
d_conc <-
  d_raw |>
  filter(EVENT == 1)

o_conc <- PKNCAconc(data = d_conc, DV~TIME|DRUG+ID)
d_intervals <- data.frame(start = 0, end = 24, auclast = TRUE)
o_data <- PKNCAdata(o_conc, intervals = d_intervals)
o_nca <- pk.nca(o_data)
summary(o_nca)

Also, I'm moving this to a discussion since it is more of a question on how to use PKNCA rather than an issue that needs code changes for PKNCA.

[jeslo328]

Does it usually take long run time? Also i end up with No dose information provided, calculations requiring dose will return NA.
The way i tried to output still produce NA.

param <- simout4 %>%
filter(EVENT == 1) %>%
group_by(DRUG,ID) %>%
arrange(DRUG) %>%

     summarize(CMAX = max(IPRED),
               CMIN = min(IPRED),
               AUC6 = pk.calc.auc.last(IPRED,TIME),
               AUC = pk.calc.auc.last(time=as.numeric(TIME), conc=IPRED))

[billdenney]

Normal run time is not long. Calculating NCA for a typical clinical study (~20-200 NCA profiles) takes a second or less. If you are calculating for many simulations (more than 1000), then it can take a while.