Choices for Area Under the Curve (AUC)

William Denney

Introduction

Area under the curve (AUC) has many versions, and subtleties in differences between AUC types can lead to selecting the correct (or incorrect) one for an analysis.

single_dose_oral <- function(t=0:24, F=1, D=1, ka=0.5, Vd=10, ke=0.01) {
  F*D*ka/(Vd*(ka-ke))*(exp(-ke*t) - exp(-ka*t))
}

simdose <- data_frame(time=0:48,
                      ke=0.1,
                      half.life=log(2)/ke,
                      concentration=single_dose_oral(t=time, ke=ke),
                      measure_type=factor(
                        case_when(time <= 24~"Measured",
                                  time > 24~"Extrapolated"),
                        levels=c("Measured", "Extrapolated")))
simdose <-
  bind_rows(simdose,
            simdose %>%
              filter(time == 24) %>%
              mutate(measure_type=factor("Extrapolated",
                                         levels=levels(simdose$measure_type)))) %>%
  arrange(time, measure_type)

ggplot(simdose, aes(x=time, y=concentration, linetype=measure_type)) +
  geom_line()

For the above concentration-time curve