pkm: Posterior concentration estimates

View source: R/pkm.R

pkmR Documentation

Posterior concentration estimates

Description

Fits a two-compartment model to obtain posterior estimates of concentration of drug over time.

Usage

pkm(
  formula,
  data,
  subset,
  ivt,
  pars = c(getOption("pkpredict.pip.default.prior")$log_pk_mean,
    getOption("pkpredict.pip.default.prior")$log_err_mean),
  alp = 0.05,
  cod = 12,
  thres = 64,
  timeint = c(0, max(sapply(ivt, function(x) x$end)) + cod),
  mcmc = FALSE,
  nreps = 5000,
  nburnin = 2000,
  nthin = 10,
  seed = NULL,
  shiny = FALSE,
  ...
)

Arguments

formula

A formula where the left side is the measured concentration of drug and the right side is the times of concentration measurements

data

Data frame with concentration data (time of measurement in hours and concentration in mcg/ml)

subset

Subset of the dat data frame to use

ivt

List with containing start of infusion times, end of infusion times, and rate of infusion at each dose

pars

Vector of (prior) log-pharmacokinetic parameters of length 5: (lv_1, lk_10, lk_12, lk_21, lerr)

alp

Value of alpha to use for generating pointwise (1 - alp)% confidence bands

cod

Length of time after end of last dose to consider

thres

Threshold for effective treatment (mcg/ml)

timeint

time interval over which to compute estimate

mcmc

logical: should estimate of time above threshold be computed using MCMC (false = laplace approximation)

nreps

number of MCMC iterations to perform (including burn in)

nburnin

number of burn in replications to perform

nthin

mcmc thinning interval

seed

seed for replicating MCMC results

shiny

is this being used within shiny_pkm

...

additional arguments (e.g., 'mu', 'sig', 'ler_mean', 'ler_sdev' for changing the PK parameter prior mean, variance-covariance matrix and error prior mean and standard deviation, respectively)

Details

Measurements must be entered in particular units: mcg/ml for concentrations, g/h in rate of infusion, hours for times.

Value

posterior estimates

Examples

ivt_d <- list(list(begin=0.0, end=0.5, k_R=6),
              list(begin=8.0, end=8.5, k_R=6),
              list(begin=16.0, end=16.5, k_R=6))
dat_d <- data.frame(time_h = c(1,4,40), conc_mcg_ml = c(82.7,80.4,60))

pkm(conc_mcg_ml ~ time_h, data = dat_d, ivt = ivt_d)

hlweeks/pkpredict documentation built on Oct. 29, 2023, 6:08 a.m.