fit_prespecified_model

Description

generates nlme::lme model either prespecified or without TRT and TIME.

Usage

fit_prespecified_model(
  data,
  dv_col,
  id_col,
  conc_col,
  delta_bl_col,
  trt_col = NULL,
  tafd_col = NULL,
  method = "ML",
  remove_conc_iiv = FALSE
)

Arguments

Name	Description
data	a dataframe of the QTc datset
dv_col	an unquoted column name of dependent variable data
id_col	an unquoted column name of ID data
conc_col	an unquoted column name of CONC data
delta_bl_col	an unquoted column name of delta_bl values, e.g. deltaQTCFBL, deltaHRBL
trt_col	Optional - an unquoted column name of TRT data
tafd_col	Optional - an unquoted column name of TAFD data
method	method for nlme::lme fitting
remove_conc_iiv	boolean for removing IIV on concentration slope parameter

Returns

an nlme::lme model fit to the data

Examples

data <- preprocess(data)

 fit_prespecified_model(data, deltaQTCF, ID, CONC, deltaQTCFBL, TRTG, TAFD)

Model Equation

$$\begin{aligned} \Delta \text{QTcF}_{i,j,k} = & \left( \theta_0 + \eta_{0,i} \right ) + \left( \theta_1 + \eta_{1,i} \right ) C_{i,j,k} + \theta_2 \left( \Delta\text{QTcF}_{i,j,k=0} - \text{QTcF}_{\text{baseline}} \right ) \\ & + \theta_3 \text{TRTG}_j + \theta_4 \text{TAFD}_k \end{aligned}$$

Reference

Garnett C, Bonate PL, Dang Q, Ferber G, Huang D, Liu J, Mehrotra D, Riley S, Sager P, Tornoe C, Wang Y. Scientific white paper on concentration-QTc modeling. J Pharmacokinet Pharmacodyn. 2018 Jun;45(3):383-397. doi: 10.1007/s10928-017-9558-5. Epub 2017 Dec 5. Erratum in: J Pharmacokinet Pharmacodyn. 2018 Jun;45(3):399. doi: 10.1007/s10928-017-9565-6. PMID: 29209907.