Use weight-based dosing for a population within add.dosing()

[SGastine]

Hi,
I have a new issue when using RxODE 1.1.5.
With the previous version I was able to pull in covariates from pre-defined populations into my event tables. Now I get an error message that dose within add.dosing can only have length 1.
It was quite a neat feature to simulated complex weight and bsa-based regimen. Is there a way to get this working again?

Thanks!
Silke

Here is my example code:

e_1 <-   et(id=sim.cov$id) %>%
  add.dosing(start.time = 0,dose = 600000*sim.cov$wt, nbr.doses = 14, dosing.interval = 8, dur=15/60) %>% 
  add.dosing(start.time = (5+9)*24,dose = 600000*sim.cov$wt, nbr.doses = 14, dosing.interval = 8, dur=15/60) %>%
  add.sampling(seq(from = 0, to = 24*21, by = 0.25)) %>%
  as.data.frame %>%
  merge(sim.cov, by="id") 

[mattfidler]

#475

[mattfidler]

Hi, @SGastine

Indeed this can be useful. I have opened a feature request in rxode2, as I no longer develop this package.

In the mean-time you can still do weight based dosing as follows:

library(RxODE)
#> RxODE 1.1.5 using 4 threads (see ?getRxThreads)
#>   no cache: create with `rxCreateCache()`

sim.cov <- data.frame(id=1:10,
                      wt=rnorm(10, 70, 10),
                      sexf=round(runif(10)))

e_1 <-   et(id=sim.cov$id) %>%
  add.dosing(start.time = 0,dose = 600000, nbr.doses = 14, dosing.interval = 8, dur=15/60) %>%
  add.dosing(start.time = (5+9)*24,dose = 600000, nbr.doses = 14, dosing.interval = 8, dur=15/60) %>%
  add.sampling(seq(from = 0, to = 24*21, by = 0.25)) %>%
  as.data.frame %>%
  merge(sim.cov, by="id")

e_1$amt <- ifelse(is.na(e_1$amt), NA_real_, e_1$amt / e_1$wt)

print(head(e_1))
#>   id time      amt ii addl evid  dur      wt sexf
#> 1  1 0.00       NA NA   NA    0   NA 90.4123    0
#> 2  1 0.00 6636.265  8   13    1 0.25 90.4123    0
#> 3  1 0.25       NA NA   NA    0   NA 90.4123    0
#> 4  1 0.50       NA NA   NA    0   NA 90.4123    0
#> 5  1 0.75       NA NA   NA    0   NA 90.4123    0
#> 6  1 1.00       NA NA   NA    0   NA 90.4123    0

^{Created on 2022-05-30 by the reprex package (v2.0.1)}